Over the course of ten years of classroom teaching, I took off only one summer. And by “took off,” I mean no attending conferences, no teaching summer school, and no working other jobs. I used those four weeks for reading, writing, watching all the movies and TV I’d missed during the school year, working on my house, and spending time with my family. The two final weeks of my summer break were spent mostly lesson planning and prepping for the year to come.

So, when I got the assignment to write about teacher salaries, I thought about all the teachers I know and, honestly, I couldn’t think of a single one who didn’t have some other source of income besides their teaching paycheck. And may that’s because teachers are naturally active people who are always on the go and don’t want a single moment of rest. But, it’s probably got a lot to do with how underpaid teachers are.

The Organization for Economic Cooperation and Development examines education systems around the world. Their findings tell us what those of us in the profession have always known, American teachers work a lot of hours for not a lot of pay. Elementary school teachers in the U.S. make only 67% of what other college-educated workers make, and that’s including those in non-professional fields. High school teacher fare slightly better at 71%.

On top of that, American teachers spend an average of 12 hours a day at work. The standard school day lasts about 8 hours, though teachers are generally required to arrive one hour before the start of school. The three hours a day after school and/or on weekends include, among other things, grading, making calls, attending meetings, holding conferences, planning, prepping, and answering emails. With the estimated average salary for an American school teacher at $49,000, teachers are making about $22/hour (minus all the personal money they spend on their classrooms and students).

To put these stats in perspective, the Oklahoma 2016 Teach of the Year, Shawn Sheehan, earns a $35,419 salary.

So, until teacher pay keeps pace with cost of living (it doesn’t in 30 out of 50 states), those teachers who stay in the profession will continue to have to take on other work to make ends meet. To find out just what kind of work is sustaining this country’s educators, I reached out to teachers on social media.

Here’s what I found:

1. They use their teaching gifts in other ways.

Many teachers responded that they tutored privately. Some found their own gigs by posting or answering ads on local Craigslists sites. One teacher, Sarah, found her tutoring job this way. She put up an ad and was contacted by a businessman who wanted to pay for a tutor for one of his employee’s children. She met the student at a local library twice a week for an hour and a half. Other teachers work for companies that pair them with students and offer prepackaged curriculum. Still others have joined the online tutoring and teaching revolution.

2. They contribute even more to their school community.

The teachers who responded also make money by taking on extra work at school. Some teach summer school or worked in the afterschool program. Others lead their grade levels or departments and received stipends for that work. Some attend conferences and became program leads who are paid to deliver workshops and trainings. My mom is a middle school math teacher who has always been pretty logical and computer savvy. She spends her summers creating class and student schedules for the whole school.

3. They share their curriculum development skills.

Teachers Pay Teachers (TPT) was at the top of the money-making list for many respondents. TPT is a marketplace that allows teachers to post and sell worksheets, books, and all kinds of products they’ve created. Kim, a teacher in Austin, TX, used the revenue from her TPT shop to pay for grad school. She says, “The majority of stuff I put on there I use in my classroom, so it’s stuff I would’ve made anyway.” Teacher, Erica, agrees. She says of TPT, “It’s stuff you already use and really believe in. And this lets other teachers use it, too.”

4. They get outside.

Another common side hustle for teachers is the role of camp counselor. Teachers can be found leading groups of campers in arts, STEM, and even LEGO-related lessons during the summer months. Some teachers even have their lifeguard certification to work at city pools and summer camps.

5. They serve the community around the school.

The service and retail industries love to employee teachers. A few teachers I spoke with are bartenders on weekends and during the summer. One teacher explained that being a teacher often helped her get more tips when she was tending bar. “I think people felt sorry for me, that I was working a second job. But I loved it.” Others spent summer months hawking peanuts and taking tickets at local baseball stadiums. Hotels also like to hire teachers as housekeepers during those busy summer months.

6. They are entrepreneurs with talent.

Many of the teachers who responded had skills that they offered to teach other through private lessons, such as playing piano, skiing, golfing, and singing. They also used these talents to form bands or arrange for paid performances. Others use their woodworking and construction skills to do home repairs on weekends. Some crafty teachers use the school year to knit, sew, and built products and then take them to fairs and sell on Etsy or other online marketplaces. Mitch, a teacher in Austin, started creating print-on-demand t-shirts. He shares information about this process on his Mitch on Merch YouTube channel and says the money coming in through the t-shirts has allowed his family to buy the supplies to start their own barbecue restaurant.

7. They are salespeople.

The direct sales phenomenon has been a big money maker for some teachers. Brands like Limelight, Jamberry, and Lularoe allow teachers to sell products to their friends, family, and social media followers all from the comforts of home. This gives some teachers a sense of balance because they can be at home with their family and not always heading off to another job outside of the house.

8. They move to make money.

Teachers who live in areas where tourists flock in the summer have figured out that moving makes money. They rent out their houses and move into campers or in with family. Sites like AirBnB have made the process so easy. Some teachers also house sit during the summer while local families head out on vacation.

Teacher burnout is real. And it’s clear from all of these side hustles that teachers are working a lot, both in and out of the classroom. If you’re a teacher with a side gig, we’d love to hear from you. What do you do to make ends meet and what do you think can be done to close the wage gap?