Most of the games on multiplication.com are just poorly designed. They have the same design for the math questions all the time and they don't even fit the game. Also, the games are really buggy, like with collisions or even game mechanics. Also, the developers are literally stealing games. What to know what I mean? Look up Tricky Ball on Google and click on the third link. You get all of the levels without multiplication questions! Overall, multiplication.com is just really bad and even stealing games. You should not pay for the premium membership, it's just letting them steal more games and getting away with it.