Back-to-school shopping is a great time to teach your children some shopping skills, says Mainstreet frugal columnist Liz MacKay.

"I'm a very rule oriented person," said MacKay. And she said laying down those rules can turn the chore of buying school supplies into a learning opportunity, and make the whole business a little easier.

Here are five tips she shared:

1. Set a budget

This should be obvious, but it's important to set a budget, and let your children know what it is expected to cover.

This will help them understand how to put a budget together.

2. Buy your own upgrade

MacKay said it's important for her children to earn money as well.

Her older children have paying jobs, and the younger ones earn money from lemonade stands, collecting bottles, walking the dog, and other odd jobs.

"When children use their own money they often don't have to spend it as quickly," she said.

"If they want to upgrade it to a fancy, zipped binder, or some fancy pencil case or something like that, then they can shell out the extra money."

It is possible for them to work within the budget to get what they want, she said. Once, one of her children got one large specialty binder, rather than the four smaller ones in the budget, for the same price.

3. Consider quality

MacKay said her family has a backpack that has held up for 11 years, and has been used by all five of her children, and still doesn't have any holes.

4. Watch the sales

If your child wants an upgrade, show them how to watch the sales and see if the item they're looking for comes down in price.

"I want them to be watching those sales because they need to learn how to shop," said MacKay.

5. Wait before you buy

"There are no impulse buys. No matter what," said MacKay.

"They have impulse buys all the time. They just want stuff."

The rule in MacKay's house is you have to wait 24 hours if you see something and want to buy it. Often as not, she said, the cherished item is forgotten by then.

With files from Mainstreet P.E.I.