The first square I crocheted is called 12" Granny (free pattern). Mine turned out 10 inches big but I think if I block it, it might end up close to 12 inches.
The second block I made is called Squaring the Big Circle (another free pattern!). This is probably my favorite of the two blocks I've made so far! It came to 10 inches as well.
I've already started working on my third square, I'm getting a bit hooked on this project so I don't think it's going to take me too long to get it finished.
Have a great day!