Learn the basics of wearable electronics by creating simple sewable LED circuits. This lesson is perfect for beginners and can be adapted for all ages. No programming required!

Kit List

  • Sewable LEDs (or regular LEDs with long leads)
  • Coin cell battery (CR2032)
  • Sewable battery holder
  • Conductive thread
  • Regular thread (for securing)
  • Needles
  • Scissors
  • Fabric or felt to sew onto
  • Fabric marker or chalk

Understanding the Circuit

A simple LED circuit needs:

  • Power source - The coin cell battery provides the electricity
  • LED - Converts electricity into light
  • Conductive path - The conductive thread carries electricity from the battery to the LED
Important: LEDs have a positive (+) and negative (-) side. The positive side must connect to the positive side of the battery, and the negative to negative. If connected backwards, the LED won't light up!

Lesson Structure

Starter: Circuit Planning (10 mins)

  1. Draw your design on paper first
  2. Plan where the battery and LEDs will go
  3. Draw the path the conductive thread will take
  4. Remember: positive and negative paths must NOT cross!

Main Activity: Sewing the Circuit (30+ mins)

Step 1: Prepare your fabric

  • Mark where the battery holder will go
  • Mark where each LED will be placed
  • Lightly draw the thread paths

Step 2: Sew the battery holder

  • Use conductive thread
  • Make 3-4 tight loops through each hole
  • Leave long tails to continue the circuit

Step 3: Create the positive path

  • Sew from the positive (+) side of battery holder to the positive side of your LED
  • Keep stitches close together for good conductivity
  • Tie off securely at the LED connection point

Step 4: Create the negative path

  • Cut a new piece of conductive thread
  • Sew from the negative (-) side of battery holder to the negative side of your LED
  • Make sure paths don't cross!

Step 5: Test and troubleshoot

  • Insert the battery (+ side up usually)
  • If LED doesn't light, check connections and polarity
  • Look for loose threads or crossed paths

Troubleshooting Tips

  • LED not lighting? Check battery polarity and that it's making good contact
  • Dim LED? Your conductive thread path may be too long or connections too loose
  • Intermittent light? Secure all connection points with more loops
  • Short circuit? Look for places where positive and negative threads touch

Extension Activities

  • Add multiple LEDs in parallel
  • Create a simple switch using a snap or button
  • Design a wearable badge or patch
  • Add LEDs to a hat or bag