Some Oxfordshire Primary teachers have been experimenting with using Scratch in the Primary Classroom. A new version of Scratch has been developed called BYOB (Build Your Own Blocks) which was intended to extend the functionality of Scratch by allowing users to create a block (like a sub-routine) once then re-use it was they need. This has the added advantage that you can edit the original block and all of the places where it has been used will change automatically!
For Primary Scratch can be used as a replacement for Logo. You can get Scratch to create a simple square using similar language to Logo, but by building graphical blocks instead of typing FD 10 and RT 90 etc! The advantage of BYOB is that you can then put these little programs, for example the square, into a block (a sub-routine) then use this block to make a more complicated shape… just like sub-routines in Logo!
Take a look at http://byob.berkeley.edu/ as an alternative to downloading and using Scratch!