For Teachers

The five-minute bell-ringer routine

1. Project it. Open the daily puzzle on the board. Everyone sees the same ball, the same walls, and the same target.
2. Let them commit. Ask where the ball lands. Hands, whiteboards, or a quick vote — the point is that everyone picks before anyone knows.
3. Send one student up. They use the built-in drawing tool to trace the class's predicted path directly on the board, bounce by bounce, while the room tells them where they're wrong.
4. Fire it. The ball travels the real path. The drawn line stays on screen next to it, so the gap between what they predicted and what happened is visible to everyone at once.
5. Ask why. Thirty seconds on what the drawn path got wrong is where the physics actually lands.

The daily puzzle runs three levels in sequence — easy, then medium, then hard — so the difficulty climbs on its own while the class warms up. Play level one on a short day and all three when you have the room's attention.

One thing to plan around if you teach several sections: the daily is one run per browser per day, so period two on the same computer would arrive at period one's solved board, drawn path and all. For your later classes, open Endurance mode instead — every round is a brand-new board, so each section gets a fresh puzzle and a run of its own.

Why it works on the first day of school

Most first-week activities need students to already know something, or need you to explain a game before anyone can play it. This needs neither. The rule is visible in the first bounce, so a student with no physics background can form a real opinion in about ten seconds — and defend it. That makes it unusually good at the thing day one is actually for: getting a quiet room to argue with each other in front of you.

It also survives repetition. A new puzzle appears every day, so the same routine that broke the ice in September is still a working warm-up in November, with no effort from you.

The physics inside

Bounceplot runs one rule, cleanly: no gravity, straight lines between collisions, perfectly elastic bounces, and angle in equals angle out. Because nothing else is happening, students can reason their way to the answer instead of guessing — and when they miss, the miss has a single, findable cause.

It supports instruction toward the law of reflection, angle measurement and estimation, and spatial reasoning with a grid. The classroom routine above is a small, honest instance of NGSS Science and Engineering Practice 7, engaging in argument from evidence: students make a public claim, commit to it, watch the evidence arrive, and revise. We are describing what the activity supports, not claiming any certification or formal alignment.

What you are actually getting

• Free. No trial, no classroom tier, nothing to buy.
• No student accounts. Nobody signs up, so we hold no student names, emails, or work.
• No ad networks. The only promotions are our own — panels beside the board for another game we made. We also load Google Analytics and a Google Ads tag; both are in our privacy policy.
• Any browser. Chromebooks, smartboards, whatever the cart has.
• New every day. A fresh puzzle each morning, plus Endurance mode when one board is not enough.

Questions teachers ask

Is Bounceplot free for classrooms?

Yes. The daily puzzle and Endurance mode are free, with no trial, no classroom tier, and nothing to purchase.

Do students need accounts?

No. There is no sign-up and no login. Because we never create student accounts, we never collect student names, emails, or work — there is no student data to protect, request, or delete.

Will it work on our devices?

It runs in any modern browser, including Chromebooks, and it is built for a projector or smartboard: high contrast, few elements on screen, and one thing happening at a time. Nothing to install and nothing to print.

I teach several sections. Can each class play the daily puzzle?

The daily puzzle is one run per browser per day. Once a class finishes it, that browser shows the completed board with the drawn path still on it, so a later period would arrive at the answer the previous class already drew. For your other sections, open Endurance mode instead: every round is a brand-new board, so each class gets a fresh puzzle and its own run to argue about.

Are there ads?

No ad networks and no third-party advertising. The only promotions are our own: side panels beside the board and a card after the daily, all pointing to Triopole, another game we made. We do load Google Analytics and a Google Ads conversion tag, both disclosed in our privacy policy.

How much prep does this take?

None. Open the page, project it, and play. A new puzzle is generated every day, so there is nothing to plan, rotate, or refresh.