Language using turtle graphics famous for teaching kids

 QLogo is an interpreter for the Logo language written in C++ using
 Qt and OpenGL. Specifically, it mimics (as reasonably as possible)
 the UCBLogo interpreter developed at U.C. Berkeley. In fact, the
 UCBLogo manual describes about 99.9% of the functionality. You can
 find the UCBLogo Manual here:
 http://people.eecs.berkeley.edu/~bh/usermanual