The day Lisa Collum started her side hustle in 2011, she went to OfficeMax and bought five binders with the last $99 in her checking account, she says.

She filled them with copies of her fourth- and fifth-grade writing curricula, sliding pages reading "Top Score Writing by Lisa Collum" into the front plastic covers. As she sold them, the five binders became 10, then 20. Within five years, she was selling hundreds at a time from her living room's makeshift assembly line, with her 8-year-old operating the three-hole-punch.

Today, Collum, 41, is the CEO of Palm Beach Gardens, Florida-based Top Score Writing, which sells K-12 writing curricula and consulting services to schools and teachers across all 50 U.S. states, she says. Her teaching approach comes from her experience helping fourth graders — many of whom spoke English as a second language — write highly structured essays, and watching their writing test scores rise, she says.

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The side hustle outpaced her $40,000 annual teaching salary within four years, she says, and became her full-time job in 2015. That same year, Collum used funds from her business to buy Coastal Middle and High School, a nonprofit private school in Lake Park, Florida.

Top Score Writing now has six full-time employees, 10 part-time staffers and nearly $1.9 million in annual profit last year, according to documents reviewed by CNBC Make It.

It's all a surprise to Collum, she says: When a school principal first asked to buy a writing curriculum from her, she laughed and responded, "There's not an ounce of business in me. I can't write this down and sell it."

From schoolteacher to CEO

Collum started her teaching career while in her 20s at the Village Academy School in Delray Beach, Florida. She noticed that her fourth-grade students, many of whom spoke English as a second language, were intimidated by the essay portion of the state's annual assessments — so she spent her first year teaching them how to plan and write introductory, body and conclusion paragraphs.

In her first semester, 95% of her students passed the state test, up from 38% the previous year, she says. Each of the next two years, every fourth grader at her school was deemed proficient at writing, says Collum.

The jump in scores was dramatic enough to raise flags at the Florida's Department of Education, incurring two separate investigations at the school. Collum eventually became a writing specialist for her school district, and left that job for a virtual teaching position after she had her third child in 2011.

Three days later, principals from her old district asked if she'd sell them her curriculum, she says. She did, charging a mere $75 per binder. Her business grew through word-of-mouth, as local principals talked with their counterparts in other school districts, and then online once Collum digitized her curricula in 2016.

Top Score Writing's curricula and teaching plans now cost between $125 and $625 apiece, depending on grade level and services offered.

A decade's worth of budding business instincts

Initially, Collum built Top Score Writing primarily for Title I schools, which receive extra federal funding to help students from low-income families.

Tina Volanti, a former fifth-grade teacher at Clovis Elementary — a Title I school in Clovis, California — found Top Score Writing on YouTube in 2022, and thought it could help her students' Covid-disrupted writing skills. Her principal allowed her to pilot the program, and the kids became noticeably more confident as writers, says Volanti, who retired earlier this year.

Over the years, Top Score Writing found its way into schools with higher concentrations of "gifted" students, Collum says. There, its formulaic approach to writing received a more mixed reception: A regimented education that prioritizes structure over creativity helps kids learn how to take tests, but not actually write, critical parents and teachers say.

Collum has lost at least one major contract due to parent outcry, she says. Her typical response: All students need to learn fundamentals, even top students are struggling more with writing than math or reading right now and each Top Score Writing curriculum does touch on creative writing strategies toward the end of the school year.

She'll work with any school willing to buy Top Score Writing's curricula, she notes — and she's learned, largely from experience, when to trust the business instincts she's developed over the past 13 years.

"The first five years, it was really hard to have confidence in myself, even though I had data that what I was doing worked," says Collum. "I still know bumps are coming, but now I know how to take the hit and see what I can learn from it. ... I always go back to what I believe in and what I know students can do."

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