When I was a Post-doctoral fellow at University of British Columbia, I volunteered in their Problem Solving for Workshops at High Schools. Inspired by that over the years I have been trying them out in Bangalore Schools. Here are a sample: Kannada and English.
At these workshop, a set of problems of varying difficulty is handed out, with several problems chosen for focus. While students work on the problems, we interact the class observing their work. The students get pointers/encouragement from us helping them to move towards the solutions on their own. Finally the solutions are presented at a level appropriate for the accomplishments of the group. Students are welcome to work in groups and teachers are strongly encouraged to participate.
Please contact us via email at, athreya AT isibang.ac.in, if you'd like to run a workshop at your school.