The Mathematics Learning Study is a one year study of fifth grade students designed to examine how teachers’ practices contribute to students’ engagement in mathematics instruction and students’ subsequent mathematics achievement. Our perspective on engagement considers children’s cognitive, emotional, and behavioral engagement in learning. Data will be gathered in 2010-2011 in approximately 100 fifth grade mathematics classrooms. One of our goals with the Mathematics Learning Study will be to introduce new measures used to assess quality of mathematics instruction and student engagement to the fields of developmental psychology and mathematics education.