Tap the crystals to rack up points. The blue crystals are worth 1 point but are easier to catch. The purple crystals are 2 points but a little harder to catch. And the Key's are worth 10 points but come and go as the game progresses.
If you beat the score of one of the leaders, take a screenshot and post it in the comments. I'll be taking a peek at them often. Also, if you want more games and content check out my brothers page. https://scratch.mit.edu/users/udderlyfunny/