I'm a high school teacher, and I see parents make 5 big mistakes that cause them to overspend on school supplies

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• I'm a high school teacher, and I see parents spend way too much on school supplies all the time.
• Your school likely offers rentals for expensive items like computers.
• Many states have tax-free weekends, and many stores schedule school supply sales for those weekends.

As summer winds down and the new school year approaches, parents everywhere are bracing themselves for the costs associated with back-to-school shopping. Schools release lists of supplies and technology, and the cost can add up quickly. As a high school teacher, I often see families overspending and wasting money.

Parents can navigate the back-to-school shopping season without straining their budgets by incorporating some of these strategies. With a little planning and creativity, you can ensure your child has everything they need for a successful school year while keeping costs under control.

1. Rent the big ticket items from your school

The largest expenses on most high schoolers' shopping lists are graphing calculators and laptops or tablets. These can cost hundreds of dollars, and there's really no need to spend that kind of money on technology that will be obsolete within a few years.

Check with your school to see if it has a technology rental program that allows you to rent the equipment instead of purchasing it. Many schools, mine included, will rent calculators for free on a first-come-first-serve basis, and there is also a supply of laptops that students can rent from the school.

2. Use your network

Most of us know other families with kids who are just a little older than ours. These families can be a wonderful resource for upcycling old classroom materials such as textbooks, calculators, class-specific supplies, and even general resources like backpacks, notebooks, and craft supplies.

I love seeing parents making posts on local social media groups or personal pages, letting people know what they are looking for and seeing if anyone has them for free or for sale. Many people have extra classroom supplies and just don't have a person or place to give them to.

3. Mark your calendar for back-to-school sales

Many states offer sales tax-free shopping periods in the build-up to the school year starting. It may not be a huge discount, but if you bundle that with the discounts stores offer at the same time, it can be a great time to grab what you need at a reduced rate. Have your school supply list handy as soon as it's released, and pick up the items on sale when you find them.

4. Be critical of the school supply list

The supply lists that schools release are typically updated in the spring when teachers submit the list of supplies they require for students in the following year. Sometimes, the supplies are assigned to the course, and the fall teacher has no input on it. These lists can sometimes go years without being updated, so it's important to look at them with a critical eye for what's really important.

If you can identify the supplies your kids need to get through the first week of school, it often becomes apparent which supplies are actually "needed" and which ones are "nice to have."

For my math students, some don't actually need a folder because they take pictures of their notes and sheets from class and store them in a Google Drive folder.

Scissors, rulers, markers, and pencils are nice to have, but I always have a large supply of them in my room for students to use. You can always check in with your new teacher to see what is really needed from the list.

5. Check with your school for support programs

If money is tight (and even if it's not), check with your school and community to see if there are support programs for school supplies. These are often "no questions asked" programs supported by the public to help ensure that every student has what they need for the coming school year.

If you need help with school programs such as sports, field trips, activity fees, clubs, or societies, there are often fee-waiver programs that you can avail of simply by contacting your school. Your child's guidance counselor is a great first point of contact for this.

Your local United Way, religious organizations, local government, or Boys and Girls Club can also be great places to find help with back-to-school shopping.