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Chang Hsu began as a cram school owner in Hsinchu, Taiwan. When his staff defected and took every student, he was left $35,000 in debt and on the verge of giving up. He switched to online tutoring, filmed himself solving calculus problems for hours, and still struggled to stand out among thousands of videos.
In March 2020, Chang asked himself where his target audience, male college students, spent time. The surprising answer was an adult video site. He uploaded fully clothed math lessons onto Pornhub, banking on the contrast effect: amid explicit clips, a serious teacher in a hoodie would grab attention.
To maximize reach, Chang used porn-related keywords in his titles, "naked, " "threesome, " "oral sex", even though no explicit content appeared. This tactic drove his videos into search results and recommendations. Over time, news outlets picked up the story, further boosting traffic.
With 3 million views and 13,000 subscribers, Chang redirected students to paid courses on his own site and partner platforms. His annual revenue soared to nearly $270,000. To maintain viewer interest, he later invited assistants to appear in revealing outfits, always keeping lessons PG-rated but visually engaging.
Once he cleared his debts, Chang phased out porn sites and focused on mainstream channels. He announced plans to auction his iconic gray hoodie to fund free resources for rural students, demonstrating how success can fuel community support.
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