STEM
ApprenticeDojo
The trades run on maths every apprentice must get exactly right - because the number IS the safety. Ohm's law sizes a wire so it won't overheat; a cooling load sizes an air conditioner; a quarter-inch-per-foot slope makes a drain actually drain. Predict the calculation, reveal the working and the code behind it, then run the numbers yourself in the Trade lab. Real electrical, HVAC and plumbing maths - no internet. Ages 15-18.
▶ Play it nowBuilt for sittings of about 25 minutes on the screen. That is our design budget, not a measurement.
#4a5568 Characters who teach
Meet the cast
ApprenticeDojo is for ages 15-18 - no illustrated cast; the 'characters' are the four trade rules whose arithmetic IS the safety. OHM: volts push, ohms resist, amps flow - amps = volts divided by ohms, and amps are what a wire has to survive. THE BREAKER PROTECTS THE WIRE, not the appliance, so its rating can never exceed what the wire can safely carry (12-gauge copper = 20 A, 14-gauge = 15 A). THE 80% RULE: a continuous load may not exceed 80% of the breaker - rated for a sprint, sized for a marathon. SLOPE AND SIZE: a drain is a ramp for gravity at a quarter inch per foot, and an air conditioner is sized to the load (area x 25 BTU, 12,000 BTU per ton). Every calculation is computed on-device by a real, deterministic trade-math engine - nothing hand-waved, nothing leaves the device.
Ohm
Volts push, ohms resist, amps flow: current = volts / ohms and power = volts x amps, so amps are the number the wire and breaker must survive
The Breaker
Protects the WIRE, not the appliance - its rating can never exceed the wire's ampacity, so 12-gauge copper takes a 20 A breaker and 14-gauge only 15 A
The 80% Rule
A continuous load (3+ hours) may not exceed 80% of the breaker rating - a 20 A breaker carries only 16 A all day, the trades' margin of safety as arithmetic
Slope and Size
A drain slopes a quarter inch per foot so it drains without clogging, and an AC is sized to the load: area x 25 BTU, at 12,000 BTU per ton
What's inside
Learning goal
The trades run on maths every apprentice must get exactly right - because the number IS the safety. Ohm's law sizes a wire so it won't overheat; a cooling load sizes an air conditioner; a quarter-inch-per-foot slope makes a drain actually drain. Predict the calculation, reveal the working and the code behind it, then run the numbers yourself in the Trade lab. Real electrical, HVAC and plumbing maths - no internet. Ages 15-18.
How ApprenticeDojo handles your kid's data
- ✅ All progress, settings, and AI-generated content stays on the device
- ✅ No analytics, no tracking, no third-party SDKs
- ✅ Free — no ads, no in-app purchases
- ✅ No personal information collected from children — in line with COPPA (updated by the 2026 FTC amendments)
- ✅ No chat with strangers — play-together rooms use a short code and preset emotes, never typed messages