Is it illegal to buy and resell candy at school (Canada)?

hahaha, go for it!! This reminded me of when I was in high school and I used to buy chocolate bars etc. from wholesalers cheap then sell them at school. I would always be cheaper than the school canteen and still able to make heaps of cash. Not bad for a 15 yo. Also I used to buy second hand calculators from auction houses then sell these one by one at school.