Children’s birthday party?

My husband has been DMing a campaign for my 6.5 year old, 2-3 of her friends (usually just 2), me, and another dad. It has been going great and my kid is OBSESSED. She and her friends run off at the playground during recess to strategize what they’re going to do to complete their quest. It’s just so cute

She loves it so much that she wants a D&D birthday party and wants her dad to run a game. We don’t know what we’re going to do. The first session with our small group was ROUGH and I don’t want her birthday party to be like that again (trouble staying focused, not understanding how the game works, etc) but with 10 times the amount of clueless kids

I don’t anticipate there being many one offs that would be fun if we’re just stuck explaining the basics of how to play over and over. So I’m looking for ideas that would be good for a large group of inexperienced 6 and 7 year olds that might not be true D&D, but at least D&D adjacent enough to make my kiddo happy. I’m thinking maybe a modified version of Werewolf?

Has anyone ever attempted anything like this and/or have any ideas I could pass on?