I intentionally picked websites that are interactive and do not require them to log in with any username and password. I wanted this to be something they could access at anytime, anywhere, and not have to worry about log in credentials. They really seemed to enjoy having choice in exploring a variety of topics. I would say that overall, math was the most explored area, which made my math teacher heart happy!
I will continually add more websites to this Webmix as I find them. Feel free to drop any STEAM interactive websites in the comments below - I am always looking for new ones!