Why is instructional gesture ineffective in some contexts? And what is it about learners that predicts whether they will learn from gestures? This between-subjects linear measurement training study compares gesture instruction to two controls--operant action and transient action--in a diverse sample of first-grade students (N = 174, M[subscript…

Research on classroom peer effects has focused nearly exclusively on high-income countries and on academic skills. Little is known about peer effects in low-income countries and whether effects differ under different educational environments (e.g., teacher-directed versus child-centered, conditions of concentrated advantage or disadvantage). Based…

We present first-grade, second-grade, and third-grade impacts for a first-grade intervention targeting the conceptual and procedural bases that support arithmetic. At-risk students (average age at pretest = 6.5) were randomly assigned to three conditions: a control group (n = 224) and two variants of the intervention (same conceptual instruction…

This study evaluates a model for considering domain-general and domain-specific associations between teacher-child interactions and children's development, using a bifactor analytic strategy. Among a sample of 325 early childhood classrooms there was evidence for both general elements of teacher-child interaction (responsive teaching) and…

Mental abacus (MA) is a technique of performing fast, accurate arithmetic using a mental image of an abacus; experts exhibit astonishing calculation abilities. Over 3 years, 204 elementary school students (age range at outset: 5-7 years old) participated in a randomized, controlled trial to test whether MA expertise (a) can be acquired in standard…

Building on longitudinal findings of linkages between aspects of teachers' language during instruction and children's use of mnemonic strategies, this investigation was designed to examine experimentally the impact of instruction on memory development. First and second graders ("N" = 54, "M"[subscript age] = 7 years)…

Do typical arithmetic problems hinder learning of mathematical equivalence? Second and third graders (7-9 years old; N= 80) received lessons on mathematical equivalence either with or without typical arithmetic problems (e.g., 15 + 13 = 28 vs. 28 = 28, respectively). Children then solved math equivalence problems (e.g., 3 + 9 + 5 = 6 + __),…