Doodle Dump 8DDD

I doodle way too much in my Algebra class >.>
And it's worse cuz I have a bad memory so they didn't turn out right.

The Ruby and Sapphire one wasn't my idea. I just remembered it from somewhere, I think. If you know who drew an idea very similar to it, please tell me. I'd like to give credit for it even if it is a doodle.