Easy to get sidetracked
I don't think Coolmath Games is a good resource for teachers to use because most of the games students play do not teach or enforce math. If the goal is to have students practice math, other sites should be used. This resource has a variety of different games, however it does enforce much educational value to its users. I have used Coolmath as a student and none of the games I played were math related. Some of the popular games were Papa's Taco Mia or Sugar Sugar, both of which offer no educational value at all. If it were to be used as a resource tool, the teacher would have to closely monitor each student to ensure they are not playin games that don't contribute to learning.
How I Use It
I have used this website as a student, and don't remember learning math off of it.