I ran hero kids for mine, started when the youngest was the same age. When I started the content was sparse but enough, now it’s got a monster manual, loads of pre built adventures and loads of extra bits. The extra bits are really important for kids they include outline drawings of the pre built characters to colour in, monsters to colour in character minis to cut out etc etc.

This helped me massively as it’s often went, I want to play hero kids now! And whilst they sorted out who they wanted to be, and even what pet they wanted, sorted their coloured dice, I could quickly select an adventure based on time and difficulty, and pretty much jump straight in with no prep. Obviously read the rules before hand

Youalso just needed to make the enemy “death” as suitable as you think the kids could handle, from the rat ran away to you chopped it in half with an axe.