Lots of ideas from the K-12 list...many very appropriate for grade 5 and relevant to kids who like computers
Lots of ideas from the K-12 list, some of them followons to the Lawrence Berkeley Hall of Science Night...many very appropriate for K-5.
Well organized list of ideas by subject (electricity, math, life sciences, etc.)
One explanation of the laser pointer sound experiment
Good for both early grades and grades 4-5, a variation on the old "electromagnet nail" and uses a Slinky to boot
Please try harder to find something to capture your imagination...please look in these pages for a different project.