Here's the relevant bit:
Guided discovery lesson plans can be found on most topics in maths. Geometry is a particularly fertile breeding ground. Take something like circle theorems. Instead of simply explaining to students the Angle at the Centre relationship, why not have them discover it for themselves? Give them a set of blank circles, instructions to construct several formulations of the theorem, each time giving them complete freedom as to where they place their three points on the circumference, challenge them to measure the two relevant angles and then see what they notice. Students get important practice of measuring angles, a feeling of involvement in their own learning, and may even teach themselves a key GCSE topic without me needing to say a word. What could possibly go wrong?
I was particularly proud of a guided discovery task I came up with for introducing some of the more complex laws of indices to my Year 11 class two years ago. The worksheet looked like this: