Lou's Shrinky Dink Holder

I was sitting with my son this afternoon watching him color in his Shrinky Dinks. When he was done, and they were all shrunk, he was having a hard time with the included paper holders as they either didn't fit at all or would fall over. He turned to me and said he wanted to make a holder that works so they all stand up like they should. He told me he had a plan...

My son is 6 years old and I said sure son. Let's go make this holder. He told me the base should be circular and have a slot in it