Explain the main idea

Ask people to write a couple of sentences on a sticky note. Pick the question format you find most appropriate

Gather everyone’s notes to a board where everyone can see them and let people read them all before they go. Thank them for their answers but don’t criticise or evaluate them. If they are way off the mark, make new plans for the next session.

Benefits

By re-stating the main idea in their own words, they are more likely to remember it. Reading other people’s ideas will give them new perspectives. It also helps you judge whether they understood what the main idea was supposed to be.