Teachers play a critical role in society, tasked with molding young people into the adults that shape the future.

But teachers don't get paid as much as many other professionals. The median annual salary for high school teachers is $65,220, according to the Bureau of Labor Statistics. That's as compared to $130,160 per year for software developers and $145,760 per year for lawyers.

As such, many teachers might find a side hustle helps to bring in a little extra cash. On average, side hustlers are bringing in $891 per month, according to a recent Bankrate survey.

Here are three side hustles for teachers to consider.

Tutor

As people with an expertise in a given subject matter, tutoring "could be an easy way to enter the side hustle world" for teachers, says Jen Glantz, founder of Bridesmaid for Hire and the creator of the Monday Pick-Me-Up and Odd Jobs newsletter. Sites to try include the following:

• Wyzant offers one-on-one instruction both online and in person. The site features tutoring in a range of subject matters including animation, the math SATs and Spanish. Tutors set their own rates but most set them between $25 and $100 per hour, according to Sidehusl.com. Wyzant takes a 25% fee off a tutor's rate.

• Lessonface offers virtual tutoring in the arts, such as classes in painting and banjo, and in various languages. Classes can be one-on-one or in groups. Teachers set their own rates and the site takes a 15% fee for students who find them through the site and 5% fee for students tutors recruited themselves. One Mandarin teacher is currently charging $60 per hour and a knitting instructor is charging $50 per hour.

• TutorOcean is another platform that lets tutors teach online or in person in a variety of subjects from physics to essay writing. Tutors set their own rates and the site takes a 10% or 20% fee, depending on how students find the course. One math tutor is charging $25 per hour and a neuroscience teacher is charging $65 per hour.

Etsy seller

An option for teachers looking to make some passive income "is going on Etsy and creating guides," says Glantz. Another site to offer this kind of service is Teachers Pay Teachers. Both enable teachers to post the lesson plans they've used in their own classrooms and sell them to other teachers. The benefit is teachers only have to post these lessons once and they can keep selling for long after.

One Etsy seller is offering a kindergarten lesson plan for the entire school year, for example, for $3.50. A teacher on Teachers Pay Teachers is selling a first day of school activity for an 8^th grade U.S. history class for $4.

Fees on Etsy include a set-up fee, a listing fee of 20 cents per item and a transaction fee of 6.5% of the item price. Teachers Pay Teachers requires fees such as a one-time membership fee of $29 or a premium membership fee of $60 per year, among others.

Dog walker

Finally, there's a myriad of gig apps that are very easy to sign on and get into. These include DoorDash for food delivery, Lyft for rides, Instacart for grocery shopping and Rover for dog walking.

Teachers in particular have the benefit of having summers off. "A lot of these gig things are much more enjoyable in the summer," says side hustle expert Kevin Ha. He emphasizes dog walking and food delivery in particular as being gigs that are fun to do when the weather's nice.

Food delivery drivers make an average of $18 per hour, according to ZipRecruiter. Nationwide, dog walkers make an average of $15 to $24 per hour, according to Care.com.

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