How I Use It
I am an instructional coach and I steer teachers away from this website.
Leaving the incredibly outmoded design and look of the site aside for a moment, in my experience over half of the games have nothing to do with math in any meaningful way. Since there is no login there is no way to track progress or even if they students are on the right game.
The engagement is good on this site because exceedingly few of the games on this site are anything but entertainment. There is little to redeem it instructionally and there are tons of free and low cost alternatives that have actual pedagogical use.