West
REL West conducted a randomized control trial in two Western states that examined the effects of a problem based high school curriculum on students' proficiency in economics. The study found a significant positive impact for students of teachers who received receive professional development and support in Problem Based Economics compared with their peers.
The RCT summary for this project is available at http://ies.ed.gov/ncee/edlabs/projects/rct_89.asp.
NCEE/REL Evaluation Report