Prodigy Game is a math site recommended by some teachers on Twitter (see their tweets below).
There are a lot of premium features, but teachers can create virtual classrooms for free.
Here are the tweets I mentioned, as well as a video about the site. I’m adding it to The Best MATH Sites That Students Can Use Independently And Let Teachers Check On Progress.
@Larryferlazzo I would add @ProdigyGame
Ts can create units that allows Ss to play through several topics. My 6th graders loved it last yr.
— Jim Cordery (@jcordery) November 11, 2016
@Larryferlazzo I have just started using @ProdigyGame and my students are obsessed and I can assign skills and check progress!
— Liz Blose (@eduBlose) November 11, 2016