National Geographic for Kids
Anderson Elementary School http://www.nhcs.k12.nc.us/anderson/
Fun mental challenges for kids and adults. http://www.teachersfirst.com/tchr-subj.cfm?subject=mindstretchers&CFID=97659&CFTOKEN=99771116
http://www.teachers.cr.k12.de.us/~galgano/dibel2.htm