Using a cluster randomized trial, we investigated the effects of mathematics professional development on student achievement in elementary schools. Pairs of schools were matched on prior mathematics; percentage of students receiving free or reduced-price lunch and percentage of limited English proficient students were randomly assigned to two groups. One received professional development on mathematics that focuses on diagnosing student thinking and the other received professional development on formative assessment. Student-level achievement data (pretest and posttest performance on a standardized test of mathematics) were nested within grades and schools and analyzed using mixed-effects multi-level linear modeling. The results indicate students in schools that were provided the mathematics professional development had greater mathematics achievement than students in schools in a control condition. The effect held across grade levels.

使用整群随机试验，我们调查了数学专业发展对小学学生成绩的影响。两所学校在先修数学上是匹配的；将接受免费或减价午餐的学生百分比和英语能力有限的学生百分比随机分配到两个组中。一个接受数学专业发展，重点是诊断学生的思维，另一个接受数学发展评估。将学生水平的成绩数据（数学标准化考试的前测和后测成绩）嵌套在年级和学校内，并使用混合效应多层线性建模进行分析。结果表明，在控制条件下，提供数学专业发展的学校学生的数学成绩要高于在校学生。效果跨越各个年级。