Startup idea: Teacher-Controlled Blocklist for Viral Game Sites
A teacher is ready to go back to paper just to stop students playing Snow Rider 3D on school laptops. GoGuardian can't keep up with new mirror sites.
Get the PRD prompt, $9.99 Market: $163K in 3 years
r/Teachers · Sep 14, 2026 – Oct 14, 2026 · 958 upvotes
So sick of Snow Rider 3D
Read the thread · 239 comments
Teacher-Controlled Blocklist for Viral Game Sites is a startup idea for teachers and schools. A teacher is ready to go back to paper just to stop students playing Snow Rider 3D on school laptops. GoGuardian can't keep up with new mirror sites. A thread in r/Teachers drew 958 upvotes and 239 comments between Sep 14, 2026 – Oct 14, 2026. People get by with GoGuardian, Securly, and District firewalls, and that still leaves this job open. Hotness is 3.85, Hot. Strong pain. Some willingness to pay. The thread drew 958 upvotes and 239 comments. Gaps in existing tools. A few weeks of work. A first version is a moderate amount of work, about 3–4 weeks, priced between $10 and $49 a month and charged as a free tier and a paid upgrade. The pain, the source, the alternatives, the scope notes, and the questions on this page are free to read and free to build from. The agent starter prompt is the paid part. The first slice is on the page. One credit unlocks the rest, to paste into a coding agent, download as Markdown, or send as a private link.
Who has it
Teachers and schools.
- Teachers
- Schools
- B2B
- United States
- r/Teachers
What people use now
3 options, and the gap between them.
GoGuardian
Securly
District firewalls
Real gaps in the existing tools.
Teacher-Controlled Blocklist for Viral Game Sites is built for the part these leave undone.
A way through
A lightweight tool the teacher turns on per lesson, with a fast community-updated blocklist of specific viral distraction sites, independent of central IT.
MVP scope
The first version, in 3 weeks.
- 00 Goal
The one job
Teachers switch on a community-updated blocklist per class, without waiting on district IT.
- 01 Week 1
The core
Let the teacher turn blocking on per lesson, without central IT.
- 02 Week 2
The follow-through
Keep a fast, community-updated blocklist of the viral distraction sites.
- 03 Week 3
How it ships
As a browser extension that works on the pages people already use. AI helps, but the core job works without it.
- — Not in v1
Left out on purpose
Replacing GoGuardian. Version one does the one job above and stops there.
How it could charge
The business model, at a glance.
- Model
- Freemium
- Price
- $10–49 a month
- Buyer
- CompaniesA business with a budget pays
- Region
- United States
Hotness
Why it scores 3.85.
Strong pain. Some willingness to pay. The thread drew 958 upvotes and 239 comments. Gaps in existing tools. A few weeks of work.
958 upvotes 239 comments r/Teachers Sep 14, 2026 – Oct 14, 2026 verified Oct 14, 2026 Thread ↗
Weights: pain 25%, willingness to pay 20%, demand 20%, gap 15%, ease 10%, recency 10%. Recency is recomputed every build. The source report’s 1–10 score is not shown.
Market size · estimate
How big this could get
A bottom-up estimate for Teacher-Controlled Blocklist for Viral Game Sites: real customer counts × a realistic price. Not a forecast.
$36M a year
1.5M teachers · 40% of US public school teachers
$10.8M a year
450,000 teachers · schools that let teachers add tools
$163K a year
6,800 teachers · 1.5% of the reachable segment in three years
What that means
6,800 teachers at $2/mo = $163K ARR
Low confidenceHow we estimated this
- Base: 3,760,000 US public school teachers.
- Has the problem: 40% (assume 40% fight game sites in class).
- Revenue per teacher: $24 per year ($24 per teacher a year).
- Reachable: 30% (schools that let teachers add tools).
- Three-year capture: 1.5% of the reachable segment.
TAM = customers with the problem × revenue per customer. SAM = the part an early product can reach. SOM = a conservative three-year share of SAM. Bars use a log scale. Shares marked “assume” are our judgment, not measured.
Source: NCES, Characteristics of Public School Teachers (2020–21)
Take it to a build
Build Teacher-Controlled Blocklist for Viral Game Sites with an agent, or with us.
Agent starter prompt
$9.99 / 1 credit
A full PRD written for a coding agent: scope, data model, screens, edge cases, and the first week of tasks for this idea.
- Copy it straight into Claude Code, Cursor, or Codex.
- Download it as a .md file you keep.
- Send your bot a private link that refreshes every seven days.
# Agent starter prompt: Teacher-Controlled Blocklist for Viral Game Sites You are a senior product engineer. Build only the product described in this document. If a detail is missing, choose the smallest option and write it down in the README. Do not invent a second product, a marketplace of marketplaces, or a growth hack. ## Product Name: Teacher-Controlled Blocklist for Viral Game Sites One line: Teachers switch on a community-updated blocklist per class, without waiting on district IT. Shape: Browser extension AI stance: AI-assisted Region for v1: United States Hotness (context only, not a requirement): 3.85 (hot). Strong pain; some willingness to pay; thread engagement 958▲/239💬 (demand 5/5); gaps in existing tools; a few weeks of work. ## Problem A teacher is ready to go back to paper just to stop students playing Snow Rider 3D on school laptops. GoGuardian can't keep up with new mirror sites. Who feels it: Teachers and schools.
The first slice is above. The rest unlocks for 1 credit and is never in this page’s HTML.
Credits work on both sites. On Business Ideas to Build the same credit unlocks the business plan and growth playbook for Teacher-Controlled Blocklist for Viral Game Sites.
Or we build it
Your first version, shipped by our team.
A working product in your repo, built from this PRD. You own the code.
$1,000 scoping fee, credited toward the build.
Equity instead of cash is an application, not a checkout →Questions
Is this idea already taken?
People already use GoGuardian, Securly, District firewalls. Those options do not do the job in the solution above. The idea is free to build. Nothing here is an exclusive claim.
How hard is a first version?
Moderate. A tight MVP is about 3 weeks (3–4 weeks), assuming the regulated or partner-gated parts are stubbed. The paid prompt turns that into tasks.
Who would pay, and how?
The audience is teachers and schools. Charge a free tier and a paid upgrade, and test a price between $10 and $49 a month. Willingness to pay is one input to Hotness, not a promise that someone will buy.
Can I use the evidence?
Yes. Build the product. The thread title is a short excerpt with a link, not a quote we are putting in someone's mouth. Exact post dates and verbatim lines are added only after a manual check. Ideas are suggestions, not medical, legal, or financial advice.
If you want the operating plan rather than the build document, it lives on the sister site. See the growth playbook