How to start homeschooling in Ontario?

I would like to start homeschooling my kids, but i am not sure how to go about starting. They are currently 4 and 5 and attend Jr and Sr kindergarden in a traditional public school. We live in Ontario, Canada. My son (age 4) is very advanced for his age, and is extremely bored with traditional JK. His cl is just barely learning their ABCs and he can read and write and do some math. My daughter (age 5) is very easily distracted in large groups, and although does great on her homework at home and enjoys doing it, has trouble focusing at school because there is so much around her to distract her. Because of these things, I think that they would both thrive in a home school environment. The only thing that has deterred me so far is worrying about cost. We are on a budget and cant afford to spend huge amounts of money on materials and supplies. I would love to get some advice from other Canadian homeschooling parents on how to go about getting started.