Use UserInfo. You can store ints and Strings over the greenfoot website. http://www.greenfoot.org/files/javadoc/greenfoot/UserInfo.html For the methods and how to use it.
MatheMagician has made some 3D games. And I think I've seen more somewhere else here, but Builderboy has been the main guy making 3D games on the website (from what I've seen.)
It looks like yo have an error. The score counter stays the same as it was at the end when you restart... I'm guessing it's static or something like that? Or you didn't properly restart it.
2013/6/10
Multi Level demo
2013/6/8
CRUMBLING TOWER
2013/6/6
Procaryota
2013/6/5
Procaryota
2013/6/4
Frog Run
2013/6/3
In Shadow
2013/6/3
Castle Storm 3D
2013/6/2
Avoid The Squares
2013/6/2
Avoid The Squares