Hi, with my year 8s next week, I want to end the lesson on a blockbusters style quiz. The kids will be in 2 (or maybe 4 teams), and will need to answer 5 questions correctly to get across the board. I had originally allocated 10 minutes for this, but would 15 be better? Is that too long for a plenary? It will tie up knowledge from that lesson and the last session. thanks!