"Good" with students learning their addition and subtraction skills.
You shouldn't use this unless your trying to just let your students play games.
How I Use It
I've had my students use this website multiple times. Yes, it does have ads that can lead to malware in computers, but I've experienced no problems with the ads, as a tell my student to not click them. But about the "math" it has pretty basic math subjects such as subtraction making good and not so good for little kids. The problem is little kids tend to not listen to you, so they might click the ads. This kills all reason of using it as it has pretty kindergarten rated math questions. You can use it to entertain the student but their basically games, as no older kids tend to do the games that actually have math in them.