The problem with a digital classroom activity is rarely the activity. It is the twenty minutes lost to accounts, passwords and a device that will not join. A virtual lock avoids all of it: you share one link or project one QR code, and every student is in the activity within seconds, with no account and nothing installed.
A dozen dozen. Three digits.
Wrong answer, try again.
Every card is a real lock, styled the way a teacher can style it. Pick one to play it in the demo. In this order they make one chained story, each reveal sending the class to the next subject.
Themes, filmed unlock animations and celebrations come with the Event Pass or Pro. Every lock format and every reveal, the sudoku, the Wordle and the HTML endings included, is free.
Lock Challenge is an online classroom escape room builder. You write a question from the lesson, choose the lock that fits the answer (a code, a word, colours, switches, arrows, a melody, a sudoku, a Wordle and more), and hide the next task, a document or a final message behind it. Students open one link or scan one QR code on any phone, tablet or laptop, with no account and nothing to install.
A multi-step escape room is a chain of locks. Each right answer opens the next step, and the last one opens the finale. Nobody can skip ahead: step two stays shut until step one is solved, so a group always works on the same question. This is the ready-made three-subject template, exactly as a class plays it.
The cupboard holds a dozen boxes of a dozen eggs 🥚 each.
🍳 The canteen takes one full box for a giant omelette.
How many eggs are left? 🔢 Three digits.
✓ Right answer: the class sees
Cupboard open.
The science cupboard opens.
Inside: a plant under a lamp, and a label whose word has been torn off.
This plant 🌱 makes its own food from sunlight, water and carbon dioxide, and gives out oxygen.
🤔 What is this process called? ✏️ One word.
✓ Right answer: the class sees
Front page.
Behind the pot, an old newspaper headline:
"ONE SMALL STEP FOR MAN"
The date has been torn off.
The newspaper 📰 tells the story of Apollo 11 🚀 and the first human steps on the Moon.
They happened in the last year of the 1960s.
Which year? 🔢 Four digits.
✓ Right answer: the finale opens, below
The last reveal, written in HTML blocks: a headline, a ticket and a stamp, in the lock's own colours.
Three subjects, one class
The classroom door swings open. Every lock gave way, and you made it out together.
Well done
Write your time on the board. The next group has a record to beat.
Door open
On the free plan you can publish 3 locks, single or multi-step, of up to 3 steps each, and they never expire. The Event Pass ($7.90 for 15 days or $9.90 for 30 days, paid once) raises that to 10 locks of 10 steps and Pro removes the limit. Each step keeps its own question, lock, hint, error message and reveal.
Play the three steps →The most useful pattern is small: one question, one answer, and the next worksheet behind it. Students who get it move on, students who do not get a hint and try again. Retrying costs nothing and is not recorded as a failure, which changes how willing a class is to guess out loud.
A numeric code for a date in history or a result in maths. A written answer for vocabulary. Ordered switches for a process that has to happen in sequence. A GPS lock for a field trip. A colour sequence for art or for a lab safety chart. The mechanic is part of the question, not decoration around it.
Project one QR code and let the room work together, or chain several locks into a trail groups follow at their own pace. A time limit adds pressure when you want it, a leaderboard adds competition when the class can take it, and a hint button keeps a stuck group from stopping the lesson.
As a homework reveal: tomorrow's answer key or the next worksheet sits behind a code that is in today's homework, and students who did the work open it at home on a phone. As a station rotation: one lock per table, one QR code on each, and a group scans, solves and moves on, each browser playing its own session. As a scavenger hunt: a QR code at each stop in the room, the library or the playground, each lock revealing the clue to the next one.
Every published lock comes with a short link and a QR code you can download. Project one for the whole class, print one per station, or drop the link into the homework. Change the clue or the answer later and the same printed code still works: it points at the lock, so you do not reprint the room when the puzzle changes.
Students do not create accounts and are not asked for anything. Player pages are noindex, so an answer key or a class document does not turn up in a search engine, and a nickname for the leaderboard is optional and free text.
Pick three to eight questions from the lesson. Each answer should be something a lock can check: a number, a word, a colour order, a direction or a melody.
A numeric code for a result in maths, a written answer for vocabulary, a colour sequence for science, arrows for orientation, a melody for music.
Each reveal holds the next clue, a worksheet, a link or a message. The last one is the finale the class opens together.
Project the QR code or send the link. Students play in any browser, with no account, and each device keeps its own progress.
Designed down to the last detail
Nothing on the screen is fixed. Pick a theme, choose a filmed object that fidgets while the lock holds and opens on video, with sound, when the code is right, then a celebration for the moment it opens. Set the typeface and size, and end on your own reveal. Your players see exactly the screen you designed.
Everything you can design on a lock →51 themes, and more in the builder. Each one paints the lock, its keys and its button.
45 filmed objects that fidget while the lock holds and open on video, with sound, when the lock gives way.
37 typefaces and 6 text sizes, from a phone in hand to a screen across the room.
Or your own two pictures
Upload a closed and an open picture: the parcel as wrapped, then what was inside. Included with the Event Pass and Pro.
Every theme, every filmed animation, your own pictures, the celebrations, typefaces and text sizes come with the Event Pass or Pro. A basic lock keeps the default theme.
Playable examples you can copy in one click. Try one first, then make it yours.
Event PassThree questions across three subjects, one shared screen, each answer opening the next. Built for a class of thirty with no equipment beyond the projector.
Locks used: Numeric code, Written answer
Available in: EN · FR · ES · CA · PT · Free to open and edit. Published with an Event Pass or Pro.
Event PassOne question, one answer, the next resource behind it. The fastest way to use a lock in a lesson.
Locks used: Written answer
Available in: EN · FR · ES · CA · PT · Free to open and edit. Published with an Event Pass or Pro.
Event PassThree rooms, three mechanics, one final code. The shortest complete escape game you can run in a single room.
Locks used: Numeric code, Colour sequence, Touch pattern
Available in: EN · FR · ES · CA · PT · Free to open and edit. Published with an Event Pass or Pro.
One question and one reveal is already a complete activity. Start there.
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