Kojo (the web version) now has a 3D Turtle, thanks to some great work over the summer (as part of GSOC) by Jerzy Redlarski! Jerzy has written a nice story introducing the 3D turtle. Check it out…
Note that in its current incarnation, the 3D Turtle is written entirely in Scala (with no dependence on any low-level 3D library), and has not seen much of performance optimization – so it’s a tad slow (but still very usable). Expect things to improve on this front as Jerzy puts in more work in this area.
Enjoy!
The Kojo Learning Environment 
The 3d canvas is pretty cool in Kojo but painfully slow. Is this still being worked on? Thanks.
This has not seen any work since the GSOC project. Contributors wanted!