3 Switch Problem Demo

About this demo

Flip switches and observe results to answer which switch is controlling an apparatus as you complete the first challenge of the 3-Switch Problem Puzzle Park. Talk to other kids who are also starting their way through the park.

This is a short game and the demo is even shorter!

Estimated completion time for this demo may be as short as ten minutes! (Estimated completion time of full game is 1 hour, give or take.)

Map

The park in the full game includes three buildings, and each building hosts three of the nine challenges. In this demo, you can access the initial rest area along with the first challenge, highlighted below.

How to play

In this demo, you can complete the first of the nine challenges.

• Each challenge has a lobby with an apparatus in an adjoining room.
• The lobby has three switches.
• One of the switches controls the apparatus in the adjoining room.
• The others do nothing.
• You must determine the active switch.
• But you can only go in the adjoining apparatus room once.
• To win the full game, you must successfully determine the active switch for all nine challenges in a row.

Only one switch is active

As a demonstration of the way the switches work, the outdoor fountain is also controlled by one switch of a three-switch panel. The difference with the outdoor demonstration is that you can actually see the fountain as you play with the switches. 

Just like the real challenges, the fountain demo will randomize the active switch each time you return, so it's not always the same switch.

Origin story: One Light and Three Switches riddle

This game was designed and created by me, Andrew MacMillan, as a way to help my kids solve the One Light and Three Switches riddle. Rather than simply telling them the answer to the riddle, I made this game.

The original riddle goes like this:

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There is a light bulb inside a closet and behind a closed door. You cannot see if the light is on or off, but you know the light is off to start. Outside the closet, there are three light switches. You know one of the switches controls the light and you are allowed to flip the switches, but once you open the door to check the light, you can no longer move the switches.

How do you figure out with certainty which switch controls the light?

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Although there are no light bulbs in closets controlled by switches in this game, my theory is that if a person can complete all nine challenges in a row, they should be pretty close to solving the original riddle too.

In any case, hope you enjoy this little game!

Andrew

ps: Full release on Oct. 26, 2026.