TechnologyThe ProfessorBeginner
Hands-On Electronics, a free technology course on Tomo

Hands-On Electronics

Demystify how everyday gadgets work by building and understanding circuits from the ground up. Learn to direct electrical currents, wire components safely, and read circuit behaviors.

Like Duolingo, but for Hands-On Electronics. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.

28 levels across 4 sections, about 56 minutes end to end, roughly 11 days at five minutes a day. It moves through The Closed Loop, Controlling the Current, Switching and Sensing, and Integrated Systems and Troubleshooting. It starts from scratch.

28 bite-size levelsAbout 5 minutes each

Free forever · No credit card · iPhone & Android

Ohmie the Owl, the guide who teaches the Hands-On Electronics course
Hands-On Electronics
with Ohmie the Owl
28
Levels
4
Sections
5
Min/day
What you'll learn

Key ideas in Hands-On Electronics

  • Electricity must complete a full, continuous loop from the power source back to ground to flow
  • A gap anywhere in the circuit halts the flow of electricity to all components in that loop
  • Voltage is the electrical pressure that pushes charge through conductors
  • Higher voltage provides more push to move charge through circuit components
  • Current measures how much electrical charge actually flows past a point per second
  • Voltage is the push that creates current, but current is the flow itself
  • LEDs are directional (polarized) and only allow current to pass in one direction
  • The longer leg must connect toward the positive power side and the shorter toward negative/ground
  • Flipping the LED 180 degrees reverses its orientation so current can flow
  • A short circuit happens when electricity takes an unintended path that skips the load entirely
  • Without resistance to slow the flow, an enormous surge of current generates rapid, dangerous heat
  • The battery and wire can become hot enough to melt plastic or burn fingers
  • Breadboard holes grip wires using internal spring tension rather than permanent solder
  • Parts can be repeatedly plugged in, unplugged, and rearranged without damaging them
  • Outer power rails (often marked red and blue) run power vertically along the entire side
  • Numbered rows in the middle connect five adjacent pins horizontally into a single node
Why not just Google it

You've tried the other tabs

Wikipedia

Thirty open tabs. Four facts you actually kept.

YouTube

You watched. You nodded. By Sunday it was gone.

ChatGPT

One answer, then back to scrolling.

Online courses

Eight weeks. You meant to finish. You didn't.

Tomo gives Hands-On Electronics the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.

Try a question

Here's what playing it feels like

A real question from this course. Take your best guess.

Completing the Circuit Loop

What happens to the components in a circuit if a single wire is unplugged, creating an open gap?

Get it right to open this lesson and 27 more in the app.

Course map

Where Hands-On Electronics takes you

  1. 1

    The Closed Loop

    • Making Your First Circuit Work
    • Prototyping on a Breadboard
  2. 2

    Controlling the Current

    • Protecting Circuits with Resistors
    • Storing Energy in Capacitors
    • Directing Current with Diodes
  3. 3

    Switching and Sensing

    • Switching with Transistors
    • Interfacing with Sensors
  4. 4

    Integrated Systems and Troubleshooting

    • Logic and Integrated Circuits
    • Finding and Fixing Circuit Faults

4 sections · 9 units · 28 levels. Built to play, not to enroll.

How it's taught

You pick the voice

This course
The Professor

Hands-On Electronics is taught in the The Professor style: clear, structured, thorough. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.

Keep going

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Start free

Start Hands-On Electronics today.

Download Tomo, search Hands-On Electronics, and play your first lesson in under a minute.