Happy City

Happy City is a design activity exploring circuits, conductivity and community. Kids add things to a city model to make it a happier place, using LEDs, batteries and motors (optional) to make their creations do something. Since the kids decide for themselves what would make the city a happy place, they become invested in what they’re making and how it will work. This kind of problem-defining and problem-solving is at the heart of engineering design. The activity can inspire great conversations about electricity or community.


activity video:

Happy City


Electricity and Magnetism

age range



  • LEDs, assorted colors, 4–6 per person

  • 3V coin cell batteries, 5 per person

  • Aluminum foil folded into wires, about 5 per person

  • Masking tape

  • Paper clips (especially helpful if you use motors)

  • Lightweight cardboard, such as cereal boxes, cut in strips

  • a wide variety of materials that can be cut, shaped and connected (index cards, straws and pipe cleaners work well. Other potentially useful materials are popsicle sticks, wire and felt.)

  • Scissors

  • Hole punches

  • markers

  • Large sheets of paper to make a city map

  • Wire (optional)

safety issues

Note – While coin cell batteries are fine to handle with your hands, they are dangerous if swallowed or put in noses. So this activity should be done with children who are old enough to resist the temptation to put everything in their mouths.


electricity, circuits, energy, engineering, making, imagination, design, problem-solving, conductivity, real world problems


New York Hall of Science (NYSCI)