Air Miles Canada has a back to school promotion where if you spend over $50 at their merchants you will receive 100 bonus Air Miles (worth $10.50 or use towards travel).

Air Miles Canada Back to school promotion.
Air Miles Canada Back to school promotion.

You will also earn 15 x the regular Air Miles (usually 1 Air Miles per $20 transaction excluding shipping, handling and taxes.

All online stores are subject to change and may be withdrawn without notice at any time. Collector must sign in at airmilesshops.ca before purchasing in order to earn reward miles. Reward miles will appear in your Collector Account within 75 days.

I personally buy a gift card where I earn the bonus miles and then use the gift card for either gifts or Christmas shopping.

Here is a link to the landing page.