Bridges: Reaching Out http://www.discovery.com/stones/techonology/building/bridges.html
Technology & Bridges Design http:projects.edtech.sandi.net/pbmiddle/bridges
Building minds: Span-It Game http:lsb.sur.edu/projects/structures/resources.html
West Point Bridge Designer http:bridgecontest.usma.edu
Bridges: Bridge Project Menu http://cl.k12.md.us/bridges/bridgept.htm
Truss Bridge Laboratory http://www.ce.ufl.edu/activities/trusslab/trussndy.html
The Bridge Challenge http://www.pbs.org/wgbh/buildingbig/bridge/challenge/index.html
NOVA Online Bridge Activity http://www.pbs.org/wgbh/nova/bridge/build.html