need help

I need to build a bridge for school. My requirments are as follows. It needs to be made of wood only but i can use glue. It must span 40 inches but no more than 46. it needs to be a min of 6 inches wide but no more than 10. we are allowed to use wood stock of 3/4 by 1/4 inches. and it can only weigh about 2.5 lbs.

 

[Qshake]

There are an awful lot of websites which show the building of bridges with popsicle sticks. The methods should suit your purpose as well.

Check out

http://www.howstuffworks.com

and search for bridges.