By Hanhui Bao, Johns Hopkins University

Most studies stop at the post-test stage, without follow-up observations. Ana Stephens and colleagues examined if an early algebra intervention had an effect on later learning.

Subjects were 1,455 students from 46 elementary schools. 716 students were from 23 treatment schools that used an early algebra intervention during 18 one-hour lessons per year from third through fifth grade during regular math class. The rest were from 23 control schools. All the students moved to a new middle school in grade 6.

Students completed an 11-item written assessment before and after the intervention. Overall, the treatment group (M = 47.51% correct, SD = 21.54%) did better than the control group (M = 37.93% correct, SD = 19.74%) in the initial year of the intervention. However, the gap between the two groups narrowed from Grade 5 to Grade 6. Control students experienced an overall increase in…