Recent work suggests that common knowledge is an important cognitive mechanism for coordinating prosocial behavior, in part because it reduces uncertainty about others' cooperative behavior. However, it remains unclear whether children also rely on common knowledge to solve coordination problems. Here we examined whether 6- to 9-year-old children…

The human capacity for technological innovation and creative problem-solving far surpasses that of any species but develops quite late. Prior work has typically presented children with problems requiring a single solution, a limited number of resources, and a limited amount of time. Such tasks do not allow children to utilize one of their…

Behavioral flexibility--the ability to tailor motor actions to changing body-environment relations--is critical for functional movement. Navigating the everyday environment requires the ability to generate a wide repertoire of actions, select the appropriate action for the current situation, and implement it quickly and accurately. We used a new,…

Friendships are important sources of support during adolescence. However, a growing literature indicates some adolescents co-ruminate, or talk with friends about problems in a way that is excessive, speculative, and negatively focused, which confers risk for internalizing problems. Still, previous research had not examined the types of problems…

Previous research shows that children evaluate the competence of others based on how effectively someone accomplished a goal, that is, based on the observed outcome of an action (e.g., number of attempts needed). Here, we investigate whether 5- to 10-year-old children and adults infer competence from how efficiently someone solves a task by…

The Good Behavior Game (GBG, Barrish, Saunders, & Wolf, 1969) and the PATHS Curriculum (Promoting Alternative Thinking Strategies; Greenberg, Kusche, Cook, & Quamma, 1995) represent 2 universal, elementary school, preventive interventions which have been shown in large-scale, randomized controlled trials to have an immediate and beneficial…

The relation to operands (RO) principles describe the relation between operands and answers in arithmetic problems (e.g., the sum is always larger than its positive addends). Despite being a fundamental property of arithmetic, its empirical relation with arithmetic/algebraic problem solving has seldom been investigated. The current longitudinal…

In the present research, we provide empirical evidence for the process of symbolic integration of number associations, focusing on the development of simple addition (e.g., 5 + 3 = 8), subtraction (e.g., 5 - 3 = 2), and multiplication (e.g., 5 × 3 = 15). Canadian children were assessed twice, in Grade 2 and Grade 3 (N = 244; 55% girls). All…

Providing equitable informal science, technology, engineering, and mathematics (STEM) learning opportunities to young children from diverse backgrounds may be a way to increase access and interest in STEM and can help to address the broader goal of increasing representation. Importantly, these learning experiences must be meaningful and engage…

School engagement in adolescence is often associated with better academic performance at school, but what are the longitudinal associations between school engagement and adult educational and employment status? The current study explored these longitudinal associations using data spanning 40-years of life, from the 1970 British Cohort Study.…

Although algebra is a prerequisite for higher mathematics, few studies have examined the mathematical and cognitive capabilities that contribute to the development of algebra word problems solving skills. We examined changes in these relations from second to ninth grades. Using a cross-sequential design that spanned 4 years, children from 3…

Family is an important context for the development of adaptive child coping. Further, both family and child coping can promote positive mental health. This study examines whether family coping predicts child coping over 1 year among Mexican-origin immigrant families. Participants included 104 families with a child aged 6-10 years (M[subscript age]…

When young children recruit others to help a person in need, media reports often treat it as a remarkable event. Yet it is unclear how commonly children perform this type of pro-social behavior and what forms of social understanding, cognitive abilities, and motivational factors promote or discourage it. In this study, 48 three- to four-year-old…

Efforts to increase moderate-to-vigorous physical activity (MVPA) in school-age children are associated with improved health, cognitive, and academic outcomes. However, questions remain about whether similar benefits are observed in early childhood. We hypothesized that motor competence, not MVPA, would be related to improved cognitive and…

Complexity is one of the major demands of adolescents' future life as adults. To investigate adolescents' competence development in applying problem-solving strategies in complex environments, we conducted a 2-wave longitudinal study in a sample of Finnish adolescents (11-17 years old; N = 1,959 at Time 1 and N = 1,690 at Time 2, 3 years later).…