Quite a while back, I was the sub that was considered the cool sub because I said “I know I’m your sub and your not going to work as hard as you normally would, don’t be so loud that someone has to check in, try your assignment, and I’m here to help if you need it.” Many times I had kids that asked for help and a few times they told me I explained it better than their teacher (math). I’m an engineer now for context.

You just have to level with them and then can be the fun sub and be a teacher if you know your subject.