Ask your teachers is this is possible, perhaps for study purposes depending on your coursework, but your school is unlikely to allow you to access eBay during school hours.
ebay
Go on Ebay
at ebay.
try eBay
The site Gumtree..... has many deals (or ebay)
http://www.ebay.com/sch/Desks-Secretaries-/63569/i.html?_nkw=school+desk
ebay, school, flea market, friends, or if it's broken enemies.
You could try donating it to a school or possibly sell it on Ebay.
YOU CAN SELL THEM ON EBAY OR AMAZON OR AT SCHOOL WITH ALL YOUR LITTLE BUDDIES
EBAY fantastic for primary school starters
I would look online at Amazon or eBay. They will have them
depends what kind of Nerf gun. but your best bet is eBay.