The 2006-11 Regional Educational Laboratory Mid-Atlantic at Penn State University has concluded a rigorous experimental study of the effect of the Connected Mathematics Project 2 (CMP2) on the mathematics achievement and engagement of grade 6 students.
CMP2 is designed to encourage students to be responsible for their mathematics learning by exploring different solution pathways, sharing their ideas with other students, listening to the ideas of others, and questioning each other.
The study, Effects of the Connected Mathematics Project 2 (CMP2) on the Mathematics Achievement of Grade 6 Students in the Mid-Atlantic Region , found that students who experienced CMP2 did not have greater mathematics achievement or engagement than comparison students who experienced other curricula. The study was conducted in 70 schools in the Mid-Atlantic region.
The RCT summary for this project is available at http://ies.ed.gov/ncee/edlabs/projects/rct_25.asp.