"Often we forget to teach thinking skills to students. Project-based learning (PBL) by design demands that these skills be taught and assessed.
Every PBL project has 21st century skills that are taught, assessed, and transferable across various disciplines."
"Here's an article by BIE that appeared in the September 2010 issue of Educational Leadership magazine from ASCD. Good for general audiences as well as educators, it explains the essential elements that make rigorous PBL different from "doing projects.""