I like Timez Attack's repeating of multiplication problems as a way to learn. Going thru the maze/paths feels like it takes too long.

Does anyone know of an alternate that checks mastery before moving on?

just to clarify- I'm not looking to make a purchase. I would like a free or trial web site.

Have you looked at Tutpup? It doesn't track mastery in the same way, but does "graduate" students from a level once they are consistently winning. Or if you are trying the systematic approach (all the x1s, then all the x2s, etc..) I seem to recall that Learning Planet Kids Spacey Math moves a level at a time.

thank you. We will give those a try.

Just found this today, http://pbskids.org/cyberchase/lucky_star/index.html

Its not all multiplication, but it seems like good math practice.

The games here are not timed and speed is not of the essence, but my kids loved http://multiplication.com when they were learning their facts and didn't need to know them quickly. There are tons of games and there is something for everyone.