u/Bubbly_Ad7064

I build EraPin — the daily where-and-when deduction game some of you have tried with your classes.

Something I keep seeing in our logs: teachers signing up after midnight. 12:01am. 1:36am. 1:45am.

So here’s what we built instead so you don’t have to stay awake ti prepare for tomorrow’s morning starter: queue the packs for your unit once, pick your class days, and EraPin publishes each morning’s rounds to your room by itself. You get an email showing exactly what your students are about to play — before they play it, so nothing lands in your classroom unreviewed.

The room is ready when you arrive. The debrief is waiting after — each round unpacked for the projector, plus which round your class found hardest, straight from their scores. No Chromebooks that day? There are printable cards.

Yesterday morning this published rounds to five classrooms in Kansas while their teacher slept. That’s the whole idea.

Set it up once, in daylight. Then sleep.
The game, 100+ packs (US History, APUSH, AP World, Regents Global, WWII, Cold War…), room codes, leaderboards, and the debrief are free — no student accounts, kids join with a room code.

Auto-publish, the cards, and per-student reports are the Pro tier, and every new account gets full Pro free until at least October 1, no card, so you can run it through September and decide.

If your unit isn’t covered, comment and I’ll build the pack. teach.erapin.com — about two minutes, even at midnight.

Third post here — I build EraPin, the daily where-and-when deduction game some of you have tried.

The South went back this week, so for the first time it was actual students playing instead of teachers testing over summer.

A Mississippi teacher signed up at 10:25 on his first morning back and had students playing at 10:31. Room code on the board, that was the setup. He ran it again with his next block two hours later, so it can’t have gone too badly. 19 of the 22 kids finished all five rounds.

Another teacher made a separate room for each of his class periods before day one, so every block keeps its own leaderboard all year.

Two things broke. A few students typed the room code into the name field, so the leaderboard had three kids named after the room — fixed now, it asks again if your “name” looks like room code.

And a teacher’s school Microsoft login got blocked by her district’s security settings. She worked around it with Gmail which she shouldn’t have had to. But that is sorted out too. School Microsoft accounts should work now, and if yours doesn’t, tell me.

After the class plays, there’s a Debrief button on the teacher side — it walks through each round on the projector (what happened, when, where, and the story behind it) and flags which round your class found hardest and which they nailed, from their actual scores. The hardest round is basically your reteach target, handed to you. It’s free

Everything classroom-basic is free and stays that way: 100+ packs (APUSH, AP World, Regents Global, Louisiana, WWII, Cold War…), room codes, leaderboards, debrief, no student accounts. New accounts get Pro (auto-publish, per-student reports, timelines) free until at least Oct 1, no card.

If your unit isn’t in the library, comment and I’ll build the pack. If you run it and it doesn’t work, please let me know.

teach.erapin.com to set up a class. Today’s round: erapin.com

Reposting on the correct day this time and apologies for breaking the marketing day rule.

Some of you tried EraPin with your classes after my last post. Thanks. This is an update on one change, because the early feedback suggests it’s doing what we hoped.

This thing started when I myself being a non history expert could not win or score in my game and started losing interest to play it. It was either you know it or you just guess blindly and don’t score which was random.

So we rewrote every clue in the game so the answer can be deduced instead of recalled. The new clues made me look at the map and try deducing when I do not know an event and every time I worked my way through and won it was a different feeling.

A 7th grade teacher in Wisconsin has been running it daily. What he told me after the change:
“Students seemed more engaged — a couple who had struggled before won, and were genuinely excited about it. It’s a great addition for kids to practice relative and absolute location in Geography.”
— Brock Saniter, Elmwood Schools

Almost every teacher I talked to after the clue change had positive feedback. They could hear students discussing rather than random guessing and that was the goal. Not to win but make them learn while enjoying. Most review games like Kahoot reward the same five kids who win every review game. Everyone else spectates and checks out.

When the task is “read this landscape” instead of “remember this fact,” a different set of kids gets to be good at it. And the skill it drills — relative location to an absolute pin, observation to inference — is the same move the map and document questions on state tests ask for.

The year guess works the same way: clues anchor you in time — “in the era of the Cold War,” “just before the Y2K scare” — and the photo’s clothing, technology, and architecture let you narrow down when within it

Other things that changed since last time, mostly because teachers asked:

1. You set the round count — same pack as a 5-round opener or a 30-round full activity.
2. 100+ packs now: all 9 APUSH periods, all 9 AP World units, the full NY Regents Global History sequence, Louisiana World History by unit, plus WWII, Cold War, Civil Rights, and dozens more. ~2,500 events.
3. Live leaderboard built for the projector.
4. Debrief for published rounds with projector view
5. Auto-publish: queue the packs for your unit, pick your class days, and each morning the next round posts itself to your room.
6. Per-student reports, plus a coverage view of which eras and regions your class has actually hit.
7. Timeline and printable cards per packs.

Being upfront: those last three are the paid tier ($59/yr).

But every new account currently gets the full Pro tier free until at least October 1, no card — so you can run everything through September and decide then.

The rest — daily game, all packs, room codes, leaderboards — is free and stays free. No student accounts, nothing to install. Kids join with a room code on any device, or you just project it.
If a unit you teach isn’t covered, say so in the comments and I’ll build the pack — the Regents and Louisiana sets exist because teachers asked. And if you tried it and it flopped in your room, I’d rather hear that than the wins.
teach.erapin.com to set up a class. Today’s round is at erapin.com.

Some of you tried EraPin with your classes after my last post here — thank you. This update is mostly about one deliberate change we made since then, because a piece of teacher feedback suggests it's doing what it was designed to do.

Two problems kept coming up in every teacher conversation:

1. **Recall games crown the same five kids.** Kahoot-style review rewards whoever already memorized the content. The students who most need a win never get one — they spectate, then check out.
2. **The skills on state tests aren't the skills daily practice drills.** The map and document questions ask students to reason from evidence — relative location, observation to inference — and the daily practice for that is usually a worksheet.

So we changed the way our clues work: every clue is now written so students can **deduce** the answer rather than guess from memory — giving every kid, not just the memorizers, a fair chance to win and learn.

Here's what a 7th-grade history teacher in Wisconsin, running EraPin daily, told me after the change:

> "Students seemed more engaged — a couple who had struggled before won, and were genuinely excited about it. It's a great addition for kids to practice relative and absolute location in Geography."
> — Brock Saniter, Elmwood Schools

The part I can't stop thinking about is *who* won. It isn't luck — it's what "deduce, not recall" means concretely. Every clue has to pass a standard we call the "curious non-historian": a person with no history background, holding a world map, must be able to reason their way to the answer. Concretely: every clue must carry at least two real geographic anchors that only intersect in one region — "where the Andes meet the Pacific, near the equator" — it is never allowed to name the country or city (that kills the deduction), each anchor is checked against the pin's actual coordinates, and it can't lean on vocabulary a novice can't act on ("a narrow sea passage", not "strait"). If a clue only works for someone who already knows the event, it fails and gets rewritten.

That's why a struggling student can beat your best memorizer: the anchors are relative location, the pin they drop is absolute location, and every round is one full rep of exactly the skill pair Brock named — the same observation-to-inference move the test questions ask for. The year guess works the same way on the other axis: era clues point at clothing, technology, architecture — material culture as evidence for *when*.

What else has changed since last time, almost all from teacher requests:

- **Pick your depth** — same pack runs as a 5-round opener or a 30-round full activity. You set the round count.
- **Packs now cover full curricula** — all 9 APUSH periods, all 9 AP World units, the complete NY Regents Global History sequence (9.1–10.10), Louisiana World History by unit, plus topic packs (WWII, Cold War, Civil Rights, French Revolution, Silk Roads…). 100+ packs, ~2,500 events total.
- **Live class leaderboard** between rounds, built for the projector.
- **Auto-publish your selected packs** — queue up the packs for your unit, pick your class days, and each morning the next round publishes itself to your room. One decision per unit instead of one per day.
- **Per-student reports and coverage** — per-student progress over time, plus a coverage view of which eras and regions your class has actually covered — the evidence you take to a gradebook, a parent, or an administrator.

Honest note: those last two are the paid tier ($59/yr — though every new account gets the full Pro tier free until at least October 1, no card). Everything else — the daily game, every pack, room codes, leaderboards — is free, no student accounts, and stays that way.

Still true from last time: students join with a room code on any device (or you just project it) — no logins, no accounts to provision, nothing to install.

If you teach a unit we don't cover, tell me in the comments and I'll build the pack — the Regents and Louisiana sets exist because teachers asked. And if you tried it and it *didn't* work for your room, I'd honestly like to hear that more than the wins.

teach.erapin.com if you want to set up a class. Daily round is at erapin.com.

I built EraPin because I wanted a daily puzzle that was less abstract than Wordle and less random than GeoGuessr. The format: 5 real historical events per day. For each one you see an archival image and a geographic clue, then you pin where on the map it happened
and slide to the year.

You don't need to know history to play. The clues are written so you can reason your way to the answer even if you've never heard of the event. It's more deduction than recall.

Free, no signup, no ads. Same five events for everyone each day, so you can compare scores with friends.

Just shipped a redesigned round screen — single screen with image, clue, and year slider, then tap to drop your pin on the map.

erapin.com if you want to try today's puzzle.

Built solo. Would love to have your feedback on the new UI and what could be done better.

A history teacher in Illinois took on my offer to build her a custom pack sent me her unit materials for end-of-year teaching, and I built Maya, Aztec, and Inca packs from them overnight. She ran the Maya pack with 27 students yesterday and emailed back saying her 6th graders "LOVED" it (her caps).

The packs run on EraPin — a free classroom tool where students see archival photos, drop a pin on a world map, and guess the year. Five rounds, ~5 minutes per session. No student accounts, just a 4-character room code.

Maya pack: https://teach.erapin.com/packs/maya-civilization
Library: https://teach.erapin.com/packs

If you have an end-of-year topic not covered in the library,
send me your scope or unit notes and I'll build a pack. That's how the Maya one happened.

Hi everyone,

Last time I posted, the feedback was clear: "Topic packs (WW2, Civil Rights) are great, but I need content that actually fits my specific curriculum framework."

I've spent the last two weeks trying to bridge that gap. I tried using AI to auto-map my 1,450+ events into specific AP and Regents units, but I'm going to be honest: it failed. It was putting 2017 events into the Cold War 1945-1991 unit and modern terrorism into WWII packs.

Rather than ship a broken curriculum, I've decided to turn EraPin into a community-curated Social Studies network.

What is ready to use RIGHT NOW: If you need a bellringer for tomorrow morning, the Topic and Era Packs are pre-filled and vetted.

Topics: Cold War, Civil Rights, WWI, WWII, Industrial Revolution, French Revolution, Holocaust, Vietnam, etc.

Eras: Age of Revolutions, Medieval, Early Modern, Contemporary, Industrial Age, Cold War Era, World Wars Era.

The "Wiki" Experiment (Your help needed): I've built the Curriculum Scaffolds for APUSH (9 periods), AP World (9 units), and NY Regents (Units 10.1-10.10). I've kept these empty for now because I want them to be curated by actual teachers, not a buggy algorithm.

Verify: Use the AI sanity check to catch obvious location/date errors before publishing.

Edit: Fix any detail instantly. It saves for everyone in the network immediately.

Fill the Scaffolds: If you teach a specific unit, drop your must-teach events into that unit scaffold. Other teachers in your curriculum see what you've built.

I need your brutal feedback: I'm a solo dev building this on weekends with my own money. I need to know:

Would you actually take 60 seconds to Add your favorite events to a curriculum unit, or is an empty framework a dealbreaker?

Are the Topic Packs (Cold War, etc.) hitting the mark for your daily bellringers?

Anything broken or confusing? Better to find it now than later.

The Specs: 100% Free

No student logins (privacy-first)

Works on any device

teach.erapin.com

If you find a mistake while planning today, don't ignore it — fix it for all of us. I'm hanging out in the comments to answer anything.

P.S. Since I'm a solo dev, I'm tracking the first 100 teachers who sign up as 'Founding Members.' I'm not sure what the future holds, but I'll make sure the OGs are always taken care of if this ever grows into something bigger