This meta-analysis explored a total of 230 effects that were extracted from 20 empirical studies on overexcitabilities (OEs) to study the relationship between giftedness and OE. Variables studied included operationalization of giftedness, use of explicit benchmarks for identifying giftedness, type of OE instrument, gender, developmental level of participants, and national setting and timing of study. Overall, there was a positive and significant relationship found between OE and giftedness with the strongest relationship being with Intellectual OE and the weakest with Sensory and Emotional OE. However, the strength of the relationship varied significantly by operationalization of giftedness, being strongest when giftedness was operationalized as previous identification as gifted and non-existent when operationalized as general intelligence or cognitive ability. In addition, when no explicit benchmarks were employed for gifted identification, there was no evidence of such a difference between the gifted and non-gifted. When comparing gifted to non-gifted students, differences were found only for high school-aged students, but not for elementary and/or middle school age or adults. The differences obtained in OE between the gifted and non-gifted are likely to be overestimated due to a presence of publication bias, that is, an overrepresentation of studies with relatively small sample sizes. Recommendations include caution about assumptions regarding the prevalence of OEs among gifted students, using OEs as indicators of giftedness in school-based referral and identification processes, and for designing affective education curricula and services targeting gifted students.

Project OCCAMS (Online Curriculum Consortium for Accelerating Middle School) is a collaboration between the Center for Talent Development at Northwestern University, the Center for Gifted Education at The College of William & Mary, and Columbus Public Schools with a goal of providing accelerated learning in language arts aimed at increasing achievement and increasing participation in advanced courses in high school among students from racial and economic subgroups underrepresented in traditional gifted education services. Using a critical technology theoretical framework that examines the impact of technology on people at the individual, educational, and global levels and addresses questions around appropriate use, accessibility, and impact, project outcomes are explored through an interpretive focus on equity, including impacts on student achievement as well as students’ subjective experiences in the program. Potential implications for broader efforts in the field of gifted education to reduce disproportionality in gifted identification and close opportunity and excellence gaps beyond gifted identification reforms are also explored.

The foundation for talent development as a framework for gifted education can be found in a synthesis of the psychological literature on creativity, eminence, giftedness, and high performance. The talent development framework acknowledges the contributions of both general cognitive ability and domain-specific abilities to achievement, as well as the malleability of these ability constructs. Talent development is also consistent with research on the contributions of non-cognitive or psychosocial factors to school achievement, as well as studies on factors that influence the attainment of scholarly productivity and artistry within specific domains of non-academic talent. Although there are several theoretical frameworks and models of giftedness, talent development, ability, and intelligence, each with varied areas of emphasis and desired outcomes, the research base and practical applications for the talent development megamodel (TDMM) can serve as a guide to leaders and school administrators in making fiscal and programmatic decisions that maximize short- and long-term impacts for individuals and society. In this article, we discuss some of the practical implications of the model for assessment, curriculum and instruction, and psychosocial development within a school context.

Design-based research is characterized as a methodology where the “outcomes” of research include new or (hopefully) improved interventions in addition to contributing to the development of theory. Rather than developing an intervention in isolation (“in vitro”) and then “piloting” the intervention to evaluate its efficacy, design-based research in education develops interventions significantly “in vivo,” and directly engages stakeholders such as learners, teachers, and local administrators, in the research and design process as collaborators (van den Akker, 2007). Project OCCAMS, an acronym for “Online Curriculum Consortium for Accelerating Middle School,” is a collaboration between university-based centers for gifted education and talent development and a diverse urban school district which adopted this approach in pursuit of a shared goal of increasing access to advanced learning opportunities for low income and diverse students in middle school and providing a new pathway for successful participation in college-level coursework in high school. The articles in this special issue collectively tell the story of the development of a novel language arts curriculum which compacts three grade levels of curriculum standards into a 2-year course of study. The program facilitates academic acceleration of many students otherwise ineligible for traditional gifted education services with a goal of placing bright but underserved students in diverse schools on a path that narrows achievement gaps with more advantaged subgroups and creates time in high school for learners to take fuller advantage of advanced learning optionsmorewidely available in high schools. The authors of these articles bring both higher education and K12 perspectives. They describe the evolution of Project OCCAMS from an experimental intervention originally perceived as somewhat radical to some practitioners to an institutionalized model that has become sustainable and has continued to grow its impact beyond the life of the grants that supported its early development. In the introductory article, Calvert, OlszewskiKubilius, Cross, and Cross describe the goals of Project OCCAMS and its theoretical underpinnings in research on academic acceleration (Steenbergen-Hu et al., 2016), talent development (Subotnik et al., 2021) and the Integrated CurriculumModel (VanTassel-Baska &Wood, 2010). The authors also describe how the features of Project OCCAMS respond to specific policy and structural barriers minoritized and low-income students face to participation in advanced learning opportunities. These barriers are identified through analyses of public data and state and local policies that unintentionally contribute to the persistent underrepresentation of diverse and lowincome learners in gifted education services and advanced coursework in secondary schools. In their article describing the content, development, and revision of the Project OCCAMS Accelerated Language Arts curriculum, Robins, Sanguras, and Carpenter describe how the Integrated CurriculumModel was combined with curriculum compacting strategies (Reis et al., 2021) and culturally responsive instructional design frameworks (Gay, 2018). The authors also describe how input and feedback from participating students and teachers contributed to the evolution of the curriculum over two cycles of testing and iteration.

Project OCCAMS (Online Consortium for Accelerating Middle School) developed and piloted an accelerated curriculum through a design-based research approach combining the Integrated Curriculum Model, principles of culturally responsive instructional design, and extensive compacting. The program created a pathway for diverse middle school students to complete a 3-year course of study in English Language Arts (ELA) in only 2 years and enter high school a year advanced of grade peers in language arts. Curricula were developed through collaboration of two university-based gifted education centers and a large urban school district. The program was designed primarily to serve students from subgroups underrepresented in gifted education who demonstrated advanced learning potential but did not yet meet state criteria for formal gifted identification. Evaluation data indicate participating students, as a group, made more rapid achievement gains in language arts than local comparison groups and equal to a comparison group of students formally identified as gifted participating in a regional talent search program. The use of a common online learning platform facilitated implementation by providing forums for collaboration and support among educators at multiple schools and universities and opportunities for continuous observation and data collection and allowed frequent iteration of the curriculum.

In this chapter, the authors present a framework for viewing curriculum that emphasizes domain-specific trajectories that start with potential and then – through opportunities and supports – move students to competency, expertise, and creative productivity in adulthood. They discuss the importance of curriculum at the potential stage that enables young students to demonstrate advanced potential, have exposure to a wide variety of subjects and domains, hone higher-level thinking skills, and develop interest and motivation. At the competency stage, curriculum needs to build foundational knowledge and skills at the appropriate pace and build psychosocial skills such as teachability, self-efficacy, and resilience. At the expertise stage, curriculum needs to give students opportunities to work on authentic problems using the tools and methods of domain experts and to acquire an identity within the domain. As individuals move beyond expertise, curriculum is self-generated but guided by mentors who assist individuals in finding a personal niche within the domain.

Talent development requires the provision of opportunities in the form of lessons, extracurricular activities, and summer programs, and is driven by expert teachers, mentors, and coaches. Research documents the importance of participation in out-of-school activities for talent development. Gifted students' participation in challenging, out-of-school activities in science, mathematics, the arts, and social leadership in adolescence has been found to predict their choice of adult occupations and their creative accomplishments. Supplemental programs are essential parts of high-quality service models for gifted students, a fact supported by the National Association for Gifted Children Pre-K–Grade 12 Gifted Programming Standards. In many rural areas, neighboring districts are close enough in proximity to allow for regular communication and collaboration. Dual enrollment allows high school students to enroll in college courses for credit prior to high school graduation.

Talent development as a framework for understanding giftedness and advancing gifted education services has gained momentum fueled in part by recent publications, discussions, and dissatisfaction with the efficacy and sustainability of traditional approaches in contemporary schools. However, the basic tenets underlying the talent development framework are new and were apparent in the writings of many distinguished individuals in gifted education in the late 1980s and 1990s including Don Treffinger, John Feldhusen, Carolyn Callahan, Joe Renzulli, and others. In the talent development framework, general ability is considered foundational to the development of more specific, domain-relevant abilities such as mathematical, verbal, or spatial abilities. Because of its emphasis on domain-specific abilities, the talent development framework acknowledges that various academic fields have unique tra-jectories. The talent development framework emphasizes the deliberate cultivation of psychosocial skills that support high achievement, rather than leaving these to chance.

Underachievement of gifted students has been a great concern for the field of gifted education. The current study reviewed 14 recent empirical studies concerning the effectiveness of underachievement interventions on gifted students’ achievement outcomes and psychosocial outcomes. Overall, there was no evidence that underachievement interventions significantly improved academic performance of gifted underachievers ( g = .09, p = .387), especially in terms of course grades. Gifted underachievers receiving interventions significantly outscored their comparison peers on psychosocial outcomes ( g = 0.22, p = .001), which consisted of a variety of measures on self-efficacy, goal valuation, environmental perceptions, self-regulation/motivation, and psychosocial functioning. Qualitative studies generally reported that gifted underachievers benefited from the interventions in terms of increased motivation for learning, improved self-regulation, and finding school more meaningful. Findings need to be viewed in light of the relatively low quality of the evidence from recent research on underachievement interventions.

The current study is part of a federally-funded three-year design-based research (DBR) project centering on creating and delivering two accelerated online English language arts (ELA) courses to high potential, socio-economically disadvantaged 7 th and 8 th graders from four school districts in a Midwestern state.Using a mixed-methods design, this study examined data regarding key components of the intervention during the first two-years of implementation.Quantitative data included students' school achievement in 6 th grade, their baseline scores on an above-grade-level ACT and ACT Engage test, and the performance of the first cohort of project students as 8 th graders on the district's ELA end-of-9 th -grade exam.Qualitative data included interviews with school staff regarding professional development, curriculum design and instructional issues, and an end-of-course student survey.Findings of this study will be valuable for iterative and continuous adjustment of the DBR project.

The Direct and Indirect Effects of School-Based Executive Function Interventions on Children and Adolescents’ Executive Function, Academic, Social-Emotional, and Behavioral Outcomes: A Systematic Review Executive function is an umbrella term for a collection of cognitive and behavioral functions such as switching focus, organizing, sustaining attention, and controlling inappropriate speech orbehavior. Similar terms include cognitive control, executive control, and everyday cognitive skills. Although there is still no unanimous theoretical or operational definition of executive functions, it is now commonly believed that executive functions are essential for purposeful, goal-directed, problem-solving behaviors and actions (Gioia, Isquith, Guy, & Kenworthy, 2000). Some researchers have characterized attention deficit hyperactivity disorder (ADHD) as executive functioning deficits and dysfunction (e.g., Barkley, 1997, 2012). Deficits or disorders of executive functions can greatly diminish a person's ability to perform in school or work environments, function independently, or maintain appropriate social relationships (Best, Miller, & Naglieri, 2011; Bull & Lee, 2014). Executive functions have attracted interest from researchers across several fields, including medicine, neuroscience, psychiatry, neuropsychology, psychology, and education. Executive function (EF) has been linked to many important aspects of child and adolescent functioning, such as academic achievement, self-regulated learning, social-emotional development, physical well-being, and behavioral problems. For example, a number of longitudinal studies and studies with national representative samples have reported that early executive function skills predict growth in academic achievement over time (e.g., Best, Miller, & Naglieri, 2011; Fuhs, Nesbitt, Farran, & Dong, 2014), although some studies have found no compelling causal connection between the two (e.g., Jacob & Parkinson, 2015). Also, improved general executive functioning ability is found to be associated with fewer behavioral problems, and vice versa (Young et al., 2009). Planning and organization, two key executive functions, are found to be the most important predictors of school grades for middle school students with ADHD (Langberg, Dvorsky, & Evans, 2013). Recently, some researchers have advocated for increasing opportunities to assess students’ executive function so that schools can add such information tostudents’ profiles, to better understanding of their academic and social-emotional status, and provide appropriate for interventions when necessary (Bracken & Brown, 2006). The currentmeta-analysis will focus on three core components of executive functions: inhibition (also called inhibitory control), working memory (or updating), and cognitive flexibility (or shifting, task-switching). We choose to focus on these components for three reasons. First, there is a strong literature base for them. Results from factor analyses of many measures of executive functions of various populations have typically identified inhibition, working memory, and cognitive flexibility as core or important constituents of executive function (e.g., Donder, DenBraber, & Vos, 2010; Egeland & Fallmyr, 2010; Gioia, Isquith, Retzlaff, & Espy, 2002; Laztman & Markon, 2010; Miyake et al., 2000). Second, some reviews have identified them as the most important executive function components based on the frequency of their appearances in literature (e.g., Best, Miller, & Jones, 2009). Lastly, the current meta-analysis intends to take a developmental perspective on executive function in a period from childhood through adolescence. Our previous narrative review of executive function literature (e.g., Steenbergen-Hu, Olszewski-Kubilius, & Calvert, 2014) found that studies of early childhood executive function predominantly focused on inhibition, working memory, and cognitive flexibility (see the Center on the Developing Child at Harvard University, 2011). Both performance-based tests and rating scales of executive function skills have been used in clinical and research settings (Toplak, West, & Stanovich, 2013). Performance-based executive function measures involve highly standardized procedures that are often administered on a one-on-one basis to assess an individual's response accuracy or speed on specific tasks. For example, the Wisconsin Card Sorting Test (WCST; Heaton, Chelune, Talley, Kay, & Curtis, 1993) assesses a person's ability to be flexible in response to feedback, avoid perseverative tendencies, and inhibit a prior response that is no longer appropriate in a new situation (Salthouse, Atkinson, & Berish, 2003). Commonly used performance-based EF measures include the WCST, the Halstead Category Test (Halstead, 1947), Trail Making Test (Lewis & Rennick, 1979), the Delis–Kaplan Executive Function System (D-KEFS; Delis, Kaplan, & Kramer, 2001) and the Stroop Test (Jensen & Rohwer, 1966). Performance-based executive function assessments are the foremost measurement tools in clinical- or laboratory-based settings. Rating scales assess executive functionin complex, daily, problem-solving situations through responses provided by either an informant (e.g., parents and/or teachers) or the examineethemselves (Roth, Isquith, & Gioia, 2005). Some most frequently used rating scales of executive function include the Behavior Rating Inventory of Executive Function (BRIEF; Gioia et al., 2000), the Childhood Executive Functioning Inventory (CHEXI; Thorell, Eninger, Brocki, & Bohlin, 2010; Thorell & Nyberg, 2008), the Behavioral Assessment of the Dysexecutive Syndrome (BADS; Wilson, Alderman, Burgess, Emslie, & Evans, 1996), the Current Behaviors Scales (CBS; Barkley, 1997), and the Deficits in Executive Function Scale (Barkley & Murphy, 2010). Rating scales of executive function have increasingly gained popularity in education and psychology. Recently, some researchers have recommended utilizing data from multiple and different measures, such as both performance-based and rating scales, and also taking into account of someother factors, such as health problems, age, and economic and cultural influences when assessing and diagnosing EF deficits (Duckworth & Kern, 2011; Randolph & Chaytor, 2013). The current meta-analysis is interested in various types of school-based nonpharmacological EF interventions for typically developing school children and adolescents across multiple disciplines. Our review of literature shows that majority of interested EF interventions fall into two broad categories: school curricula/educational programs and mind-body interventions. These school-based interventions both target on EF but differ in key design mechanisms. Table 1 presents some representative programs for these two broad categories interventions, as well as some respective representative randomized controlled trials on these interventions. School curricula/educational programs. Representatives of such interventions include Tools of the Mind (Barnett et al., 2008), Head Start REDI (Research-Based Developmentally Informed; Bierman et al., 2008; Domitrovich, Gest, Gill, Bierman, Welsh, & Jones, 2009), Promoting Alternative Thinking Strategies (PATHS) curriculum (which is a social-emotional component of the Head Start REDI) (Riggs et al., 2006), Chicago School Readiness Project (CSRP) (Raver et al., 2011), and The Incredible Years Program (Webster-Stratton, Reid, & Hammond, 2004). A theoretical mechanism of this category of interventions is that executive functions and self-regulation interplay together (e.g., Blair & Razza, 2007; von Hippel & Gonsalkorale, 2005). Some researchers have recently proposed to integrate EF into the theory of self-regulation (Barkley, 2012; Miyake & Friedman, 2012). As Bandura (1991) noted that “The major self-regulative mechanism operates through three principle subfunctions. These include self-monitoring of one's behavior, its determinants, and its effects; judgement of one's behavior in relation to personal standards and environmental circumstances; and affective self-reaction” (p.248). More specifically, such curricula and programs function on a bidirectional model of the development of self-regulationduring which cognition and emotion interact with each other (Ursache, Blair, & Raver, 2012). Based on this bidirectional developmental model, such interventions are designed to promote students’ learning, create learning environments that are predictable and supportive for students to maintain optimal emotional arousal levels, and thus develop executive functions such as the ability to pay attention and engage in self-regulated learning. For example, the Tools of the Mind curriculum was designed to use activities to target students’ EF such as the ability to take turns and to view things from others’ perspectives while emphasizing collaborative, scaffolded learning (Diamond, Barnett, Thomas, & Munro, 2007). The CSRP aimed to enhance low-income preschoolers’ school readiness by increasing their emotional and behavioral self-regulation skills through coaching and training teachers to create classroom environments that are less stressful for both teachers and students (Raver et al., 2011). Such category of curricula and programs differ in varying degrees or aspects such as the scope of interventional components or with whom the interventions need to involve in implementations, although they share a similar design mechanism. Some curricula and programs incorporate academic learning with activities to scaffold EF and/or social emotional skills. For example, the REDI intervention has four components, covering curriculum-based lessons, center-based extension activities, teacher training on instructional strategies, and students’ participation in classroom learning and various activities (Bierman et al., 2008). In contrast, others are designed to primarily focus on EF and/or social emotional skills without an academic component. For instance, activities of the Incredible Years focus on helping children with challenging behaviorsbuild social-emotionalskills (Webster-Stratton, Reid, & Hammond, 2004). In general, most of school curricula/educational programs are designed to engage multiple parties such as teachers, school counselors, students, and even parents in implementing the interventions. Mind-body interventions. This category of interventions includes some mindfulness-based practices (e.g., meditation or biofeedback) and exercise-based activities (e.g., yoga, Tai Chi, and Qi Gong) implemented in school settings. As first defined by the United States National Center for Complementary and Integrative Health (NCCIH) in 2000, mind-body interventions “employ a variety of techniques designed to facilitate the mind's capacity to affect bodily function and symptoms” (NCCIH, 2000, p.26). Needless to say, such interventions tackle a biological/physiological basis of human emotion and behavior. They are built upon a model of body-mind connection that has been utilized in many health practices such as psychotherapy (Aposhyan, 2004). In most of such programs, children and adolescents are the direct and, most often, the only target of the interventions. The rising public awareness of the importance of executive function has led to a wealth of interventions designed to promote and enhance executive function skills in children and adolescents. Commonly used executive function interventions comprise two categories: pharmacological (e.g., stimulants used to treat ADHD patients) and non-pharmacological (e.g., computerized training, cognitive behavior therapy, and school-based interventions). As is the case for pharmacological interventions, researchers have conducted a number of systematic reviews or meta-analyses to investigate how effective non-pharmacological interventions are and whether their effectiveness was supported by reliable and convincing evidence. A big portion of such reviews are conducted on clinical samples or laboratory-based settings on non-school-based interventions such as dietary (e.g., free fatty acid supplementation) and computerized training programs (e.g., computerized working memory training programs) (e.g., Karch, Albers, Renner, Lichtenauer, & von Kries, 2013; Melby-Lervåg & Hulme, 2013; Sonuga-Barke et al., 2013; Wayne et al., 2014). Such reviews may not be particularly useful and informative for stakeholders of education arena. Some researchers have reviewed the effects of school-based executive function interventions on normal children and adolescents, particularly some direct outcomes relevant to executive function, such as general EF skills and/or specific skills in inhibition, working memory, and cognitive flexibility. Most often, these researchers chose to limit their scope of reviews to one particular form of EF interventions. For example, Smith et al.'s (2010) meta-analysis synthesized randomized controlled trials on the impact of aerobic exercise on attention and processing speed, executive function, and memory performance of adults over 18 years of age (also see Maynard, Solis, & Miller, 2014; Randolph, Rosenstein, & Michaels, 2014). Additionally, there exists a number of reviews focusing on the effects of school- or home-based executive function interventions. Most such reviews examine indirect rather than direct outcomes of executive function interventions, such as academic achievement, social-emotional development, or behavioral performance. For example, Jacob and Parkinson (2015) conducted a systematic review of the association between executive function and student academic achievement in reading and math. Randolph et al. (2014) developed a Campbell Collaboration (C2) systematic review protocol on the effects of Montessori education on academic and behavioral improvements among 5-12 years old elementary students. Similarly, Maynard et al.(2014) was another C2 review protocol on mindfulness-based interventions for improving academic achievement, behavioral and socio-emotional functioning of primary and secondary students. Currently, Baron, Evangelou, Malmberg, and Melendez-Torres (2016) are conducting a systematic review concerning the effectiveness of Tools of the Mind on young children's self-regulation, particularly in comparison to other similar school curricula or programs. The What Works Clearinghouse (WWC) have also reviewed research on the effectiveness of some executive function interventions. For example, the WWC (2008) reviewed research evidence for Tools of the Mind, an early childhood curriculum for preschool and kindergarten children. They found that one study (Barnett et al., 2008) met their evidence standards, three studies did not meet their evidence standards, and seven other studies did not meet their eligibility screens. Similarly, the WWC (2011) reviewed the research evidence of the Incredible Years program (see Webster-Stratton, 2011; Webster-Stratton, Reid, & Hammond, 2004). It is noteworthy that the WWC reviews are different from Campbell systematic reviews. Specifically, the WWC reviews aim to identify the best available evidence on an educational intervention, rather than the general effectiveness of an intervention or the potential moderators of the effects. There also exist a number of reviews of studies that do not focus on executive functions but broadly investigate the effects of school- or home-based social, emotional, or behavioral interventions on normal or disadvantaged young children and adolescents. Such interventions include self-monitoring interventions (e.g., Thompson, Maynard, Bowen, & Pelts, 2013), group-based parent trainings (Barlow & Parsons, 2005), social competence interventions (e.g., Kennedy & Pigott, 2012), instructional strategies (e.g., Spivak, Lipsey, Farran, & Polanin, 2013), school-based universal interventions (e.g., Durlak et al., 2011), and after-school programs (e.g., Durlak, Weissberg, & Pachan, 2010). These reviews typically concentrate on outcomes such as reducing challenging behaviors, developing prosocial behaviors, social competence and performance, improving academic achievement in children, adolescents, or young adults. Taken together, our survey of existing and ongoing executive function interventions reviews suggests there are no systematic reviews that have all of the following three features: (a) integration of non-pharmacological executive function intervention research from fields like neuroscience, neuropsychology, and psychology with research in education, with a primary focus on serving and informing stakeholders in education; (b) inclusion of multiple types of school-based interventions for typically developing children and adolescents, such as school curricula/educational programs or mind-body interventions; and (c) examination of both direct (e.g., general or specific executive function skills) and indirect intervention outcomes (e.g., academic achievement, social-emotional development, and behavioral performance). We thus propose to conduct a meta-analysis that will have all these three features. In summary, this meta-analysis will make a unique contribution to executive function research and practice as it will focus on the efficacy of multiple school-based interventions on typically developing children and adolescents. It will integrate executive function intervention research across multiple disciplines and include various types of school-based interventions provided to typically developing school children and adolescents. It will not only examine the effects of executive function interventions on some indirect outcomes, such as academic achievement, social-emotional, or behavioral performance, but also on specific, direct outcomes, such as EF in general and/or inhibition, working memory, and cognitive flexibility. Finally, it will explicate issues of practical importance surrounding the efficacy of EF interventions, such as those regarding whether executive function interventions work but which components work and how they work, for whom they work, and in what circumstances they work. Studies of executive function interventions need to meet three key criteria to be eligible for this meta-analysis: Relevant intervention. An intervention has to be conceptually and/or operationally designed and implemented with a focus on executive function. In other words, the core purpose of an intervention in a study is to promote the development of executive functions and it is in this way that the intervention stands out from other numerous school-based education or psychological practices that may share similar goals with EF interventions for promoting academic and social-emotional outcomes. Theoretically, we select interventions following a definition that executive function isa collection of cognitive and behavioral skills and capacities essential for purposeful, goal-directed, and problem-solving behaviors and actions (Gioia et al., 2000). Operationally, we will evaluate an intervention upon two key features to determine whether it falls into one of the two broad categories of EF interventions as described in the Introduction above: school curricular/educational programs or mind-body interventions. We selected these two features on the basis of our previous research on EF (e.g., Steenbergen-Hu, &Calvert, 2014; Steenbergen-Hu, Olszewski-Kubilius, & Calvert, 2015a, 2015b) and familiarity with research literature on EF interventions after close review of approximately 100 relevant primary studies and previous systematic reviews. The first feature is that a large portion of studies of EF interventions share a common literature base, often using terminologies like executive function, executive control, inhibitory control, cognitive flexibility, task-switching, working memory, attention, cognitive control, and effortful control (more detailed EF terminologies are described in the section of Search Keywords and Terms later). The second feature is that an intervention must involve at least one component that targets either (1) some direct EF outcomes such as those concerning EF in general and/or at least one of the three key dimensions − inhibition, working memory, and cognitive flexibility; or (2) outcomes relevant toself-regulation skills, social-emotional development, or behavioral and conduct in schools. Intervention settings. Interventions must be implemented on a group or individual basis within school-based environments, such as early childhood settings (e.g., preschool, Head Start), public, private, or charter schools. Interventions implemented in clinical- or laboratory-based settings will be excluded. Interventions implemented in home-or community-based settings, such as parent training, community prevention programs, will also be excluded. Intervention duration. The length of an intervention in studies has to be in place for at least 10 hours or two weeks, as research shows that executive function interventions need to be repeated over a sustained period of time to be effective (Barkley, 2012). We describe four exemplary eligible interventions below. Tools of the Mind. Tools of the Mind, first implemented in 1993, is an early childhood curriculum for preschool and kindergarten children, based on the Vygotskian approach (Bodrova & Leong, 2007). It consists of more than 60 activities implemented over a two-year period designed to foster children's executive functions such asself-regulation, working memory, and cognitive flexibility, as well as their academic skills. Dramatic play is a key component of the curriculum, which requires teachers to engage in intensive professional development. It is actively usedin dozens of states and multiple regions in the United States and Canada (http://toolsofthemind.org). The efficacy of Tools of the Mind has been evaluated through randomized controlled trials (e.g., Barnett et al., 2008). Head Start REDI. Head Start is a program authorized by the Improving Head Start for School Readiness Act of 2007. Head Start REDI (REsearch-based, Developmentally Informed) is a federally funded randomized intervention and control group study, developed in partnership with the Head Start Program in 2003. It aims to promote school readiness skills such as prosocial skills, emotional understanding, self-regulation, aggression control, language and emergent literacy skills. The intervention is implemented through conducting professional development and mentoring with teachers to help them improve the quality of their language use, emotional support, and positive management (e.g., Bierman et al., 2008; Domitrovich, Gest, Gill, Bierman, Welsh, & Jones, 2009). Similar to Head Start REDI, the Chicago School Readiness Program (CSRP) is an intervention series that primarily supports Head Start students, particularly those who attend Head Start sites in Chicago area. Promoting Alternative THinking Skills (PATHS) Curriculum. The PATHS curriculum, established in 2000, is designed, based on neurocognitive science research of brain development and executive functioning, to be used by educators and counselors for promoting social and emotional competencies and reducing aggression and behavior problems in children in preschool through grade 6 (Riggs et al., 2006). It is typically taught two or more times per week for approximately 20-30 minutes per day. The current version of the PATHS curriculum consists of grade-specific classroom kits for Pre-K/Kindergarten, Grade 1-4, and Grade 5/6. The efficacy of PATHS curriculum has been evaluated with some randomized controlled trials (e.g.,Domitrovich, Cortes, & Greenberg, 2007; Kam, Greenberg, & Kusché, 2004). Mindfulness Meditation. Mindfulness meditation is a common form of mind-body interventions that involves practicing and engaging in a number of techniques which aim to support and improve one's physical, psychological, and emotional well-being (Tan, 2015). Mindfulness meditation is often practiced through engaging several different activities such as breathing, gentle movement, formal meditation, and discussion in a period of time that ranges from minutes to hours. During the course of such activities, one pays attention to and accepts the present-moment feelings and experience in a non-judgmental way (Baer, 2003). The rationale is that through these activities, one trains his/her mind to shift attention and increase awareness in way which are beneficial both mentally and physically. Mindfulness meditation techniques have been widely embraced by people of all ages including school children in the past decade. A growing body of research has been conducted to study the effects of meditation as well as other forms of mind-body interventions on children and adolescents EF skills such as attention and working memory (e.g., Quach, Mano, & Alexander, 2015). Unlike the three interventions above that mostly target young children, mindfulness meditation is often introduced to youth and adolescents in school settings. Eligible comparison conditions in randomized controlled trials will include traditional school curricula, waitlist control groups, placebos (no treatment), treatments as usual, or any other alternative treatment conditions set up as a contrast to the intervention conditions that allow the efficacy of interventions to be revealed. This meta-analysis will include studies with populations of typically developing children and adolescents from ages 3 to 18. There are three reasons for selecting early childhood through adolescence as the developmental period of focus in this review. First, this age range is the key developmental period during which foundational executive functions, such as inhibition, working memory, and cognitive flexibility, rapidly progress (Best & Miller, 2010; Best et al., 2009). Second, evidence supports that early childhood and adolescence are significant periodsduring which to intervene for executive function development through intentional teaching and support due to brain plasticity (Cramer et al., 2011). Lastly, selecting this age range corresponds to the main objective of this review, which is to provide evidence-based information regarding the effects of executive function interventions that can guide educational practices for children and adolescents to enhance outcomes. There will be no exclusion criteria based on study participants’ demographic characteristics. Eligible studies may have been conducted on participants of any country but must be reported in English. Studies that have no full-texts available in English will not be included as translating such studies into English will greatly extend the time needed to complete the current meta-analysis. In other words, this meta-analysis will exclude studies conducted on primarily special populations that were clinically or medically diagnosed with biological, neurological, mental, behavioral, or learning disabilities. Examples of such special populations include children and adolescents with major cognitive deficits or brain injury, diagnosed with ADHD or attention deficit disorder (ADD), autism spectrum, oppositional defiant disorder (ODD), conduct disorder (CD), or disruptive behavior disorders (DBD), or other severe disorders. Many existing systematic reviews or meta-analyses have been conducted to synthesize the effects of EF interventions on such special populations (e.g., Cortese et al., 2015). Primary outcomes. This meta-analysis will focus on two primary outcomes: direct EF outcomes and indirect outcomes. Studies that provided either direct, indirect, or both types of outcomes could be eligible for inclusion as long as they met all other inclusion criteria. Direct EF outcomes refer to those that are either directly concerning EF in general, or those that are relevant to specific components of EF, particularly on inhibition, working memory, and cognitive flexibility. More detailed information on common assessments of executive function are described in the Background section above. Table 3 presents direct EF outcomes and measures for a sample of 23 among the 45 RCTs that we have preliminarily determined to be eligible for the current meta-analysis. Indirect outcomes include those of two different types: academic and non-academic ones. Examples of academic outcomes include scores on standardized achievement or ability tests, school grades, measures of content mastery, or school readiness. Common non-academic outcomes include self-regulation skills, self-regulation skills, social-emotional development, or behavioral and conduct in schools. Secondary outcomes. Although the current meta-analysis primarily focuses on reviewing eligible quantitative studies of school-based EF interventions, we will also gather some qualitative information from eligible quantitative studies included and a selective number of high quality qualitative studies. Examples of such information include measurement issues, elements that are influential on the effectiveness of interventions that are often not assessed in quantitative manners, factors relevant to the quality and fidelity of implementations, and cost-effectiveness of intervention components. Supplementing the two primary quantitative outcomes, such information might have valuable implications for policy-makers and future practices and research. Eligible quantitative studies need to employ strong empirical experimental research designs, particularly randomized controlled trials (RCTs). Randomized controlled trials (RCTs) include, but are not limited to, parallel group trials, cross-over trials, cluster-randomized trials, and factorial trials. Studies need to employ appropriate comparison groups, which ought to resemble the main characteristics of the intervention groups in terms of the baseline measures, age, grade levels, or other demographic factors, or these features can be statistically controlled to discount the prior differences. All eligible studies have

As an educational intervention, academic acceleration is decidedly effective for high-ability students. The research support for acceleration that has accumulated over many decades is robust and consistent and allows us to confidently state that carefully planned acceleration decisions are successful. Both grade-based and content-based acceleration are effective interventions in academic and social-emotional domains for high-ability students. Grade-accelerated students generally outperform their chronologically older classmates academically, and both groups show approximately equal levels of social and emotional adjustment. Accelerated students should be expected to achieve, relative to their new grade peers, at a high level that is generally comparable to their performance in the previous grade. Such students are typically among the top 10% in a class, and they should be expected to remain in the top 10% throughout their academic careers. To be clear, there is no evidence that acceleration has a negative effect on a student's social-emotional development. Each school district should have a written acceleration policy stating that acceleration is an appropriate and effective intervention for select highly able students who have demonstrated high performance in one or more academic areas. The policy should be characterized by accessibility, equity, and openness. It should provide guidelines for the implementation of acceleration, including administrative matters, to ensure fair and systematic use of accelerative opportunities and recognition for participation in those accelerative opportunities. Finally, the policy should provide guidelines for preventing nonacademic barriers to the use of acceleration as an educational intervention and include features that prevent unintended consequences of acceleration.

As an educational intervention, academic acceleration is decidedly effective for high-ability students. The research support for acceleration that has accumulated over many decades is robust and consistent and allows us to confidently state that carefully planned acceleration decisions are successful. Both grade-based and content-based acceleration are effective interventions in academic and social-emotional domains for high-ability students. Grade-accelerated students generally outperform their chronologically older classmates academically, and both groups show approximately equal levels of social and emotional adjustment. Accelerated students should be expected to achieve, relative to their new grade peers, at a high level that is generally comparable to their performance in the previous grade. Such students are typically among the top 10% in a class, and they should be expected to remain in the top 10% throughout their academic careers. To be clear, there is no evidence that acceleration has a negative effect on a student's social-emotional development. Each school district should have a written acceleration policy stating that acceleration is an appropriate and effective intervention for select highly able students who have demonstrated high performance in one or more academic areas. The policy should be characterized by accessibility, equity, and openness. It should provide guidelines for the implementation of acceleration, including administrative matters, to ensure fair and systematic use of accelerative opportunities and recognition for participation in those accelerative opportunities. Finally, the policy should provide guidelines for preventing nonacademic barriers to the use of acceleration as an educational intervention and include features that prevent unintended consequences of acceleration.