I have been making retrieval starters on four prerequisite topics, just changing the numbers each time. Then setting them one of those 4 topics(their choice) for independent study which they show me the following week.
Our homework is on uplearn so this is extra homework for each week.

I have a similar issue with mine, although I ‘only’ have 19. The range of ability is huge and they’re not at all ready to be independent learners. It’s a struggle.