The best attempt I’ve seen at a teaching game would be Vegetato’s “GDevelop Heros”
GDevelop Heroes (Play and Learn) (Update #4)
I will say, if you do a teaching system or something like that, I’d be happy to help some tutorials or etc for it! (As long as they are easy enough to make 
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(Also, I have another idea but it’s more of an “extension” than an entire system, do you still want to hear it? 
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