This can work well by setting open-ended tasks or problems that involve a range of related mathematical concepts in the solution of the problem. Students do this in groups and very much direct their own learning. The teacher acts more like a facilitator than someone standing up the front of the class demonstrating various mathematical techniques.

Students in groups can offer different strategies to solve the problem and group members evaluate and critique the strategies of others in a productive manner until a solution to the original problem is found. This is a strategy that I have already used in senior maths classes with a good amount of success.

This is also related to the type of open-end group work mentioned above. This works well when students offer up individual strategies and solutions to problems and have to explain their own approaches and other students must evaluate them. Students can use online resources to help them develop strategies. Groups can present their solutions to the class once they have decided on the best strategy to get them as near as they can to a solution.

I have used this in maths classes especially using the Estimation-180 resources.