Some silly ideas:
- Try and find images of Teachers when they graduated (Might have to ask around for these) and people have to guess who it is now (ask consent ofc)?
- If your willing to put time into it, perhaps a statistics section, for example "XX amount of Homework was set by the History Department this year, true or false?" or similar?
Just be careful with Kahoot, especially if your doing with the whole school, since COVID, there have been a rise in the number of Online Kahoot Crashers, which flood your game with bots, and will ruin your experience.
Good luck!