www.ael.org/rel/iti

www.thirteen.org/edonline/concept2class/month10/index.html

http://askeric.org/cgi-bin/lessons.cgi/interdisciplinary

http://zubov.atmos.uiuc.edu/CLA

www.thegateway.org

www.ncrel.org/mands/docs/5-7

http://stark.k12.oh.us/Docs/units