Pre-1996 Canadian pennies are intrinsically worth more than one cent. Up to as much as 3 cents at today's copper prices:
http://www.coinflation.com/canada/
It is illegal in Canada to deface or destroy Canadian coins. It is not illegal to sort out the pre-1996 pennies, drive large quantities across border and sell them at copper scrap prices to any of the US scrap metal recycling companies. This could almost triple the results of this fund raising activity.
This copper bullion exercise could introduce the students to the concepts of fiat money, inflation, currency systems and monetary policy.
For the post-1996 pennies, the First Calgary credit union has coin machines at six of their branches that will automatically count and issue a coupon for the equivalent cash. They take a percentage. For a school project like this, I would imagine that they would waive the processing fee after a bit of negotiation and potential good publicity.