Small Basic

Microsoft DevLabs have release Small Basic, a complete programming environment for learning BASIC - albeit a sensible subset.

Cool features include an easy to use graphics mode (pixel, vector, or turtle based), intellisense (in a very cute pop-up), no line numbers, no context menus, and comprehensive documentation.

Like me, the authors believe that it is vital for children to learn to code, and there is a nice discussion of their motivations in their first blog post.