BYOB now available

Just posted by Brian Harvey to the SIGCSE-Members list:

To Computer Science educators looking for a non-intimidating but powerful
programming language for introductory courses, we offer the alpha test
version of BYOB (Build Your Own Blocks), an extension of Scratch
(http://scratch.mit.edu), which is a visual programming language for young
people in which programs are constructed by snapping together primitive
blocks that control multimedia multi-character presentations.

BYOB extends Scratch to include first class lists and first class procedures.
These additions are all it takes to enable the construction, by the BYOB user,
of arbitrary data structures (trees, hash tables, etc.)  without needing
primitive blocks for every structure.  BYOB also supports object oriented
programming, either using its native animated objects (sprites) or building
the OOP facilities explicitly, so students will understand how OOP can
actually work, based on BYOB's first class procedures.

The plan is to release the final version of BYOB 3 in August (2010), but a
public alpha test version (2.99) is available now at http://byob.berkeley.edu
along with tutorial material in the form of Scratch projects (runnable in
BYOB).  This is and will remain free software, subject to the MIT Scratch
license that sets conditions for distribution of modified versions such as
BYOB. 

-- Jens Moenig, MioSoft Corporation;
 Brian Harvey, University of California, Berkeley