Here is a Web site that talks about a project to get kids involved in computational science.
“In Project GUTS and our partnering programs, we address this urgent
need (prepared students for STEM professionals,and addressing current
complex systems issues) by introducing students to computational science starting in middle school.”
They use StarLogo TNG.
Here are some slides about the project.
http://www.projectguts.org/files/GUTS-SC-MSAC-2009.ppt ( I like slide 9 )
There are some very good video tutorials