two bricks in a school from an $89 satchel? Might one not do better there?
The satchel is really nice and I hope you ship to Ghana!
Can I make a few suggestions in order to reduce the construction cost for the school? Since there appears to be quite a bit of laterite in the area you could investigate hydraform blocks a bit further http://www.hydraform.com. The blocks use much less cement, are interlocking so construction is quicker and you need less mortar. Also the use of laterite should ensure a cooler interior.
Best of luck and we'll done.