If you’re looking for a website to help you generate writing prompts for primary school age children, then one I came across may appeal to you. It’s great fun, although the prompts it generates re, shall we say, challenging. Here’s one that was presented to me:

Write a brief biography of a sneaky rock star who is the worst singer in the world.

I’ve written more extensively about the website and where it is here:

Getting kids writing with story starters