Make a periscope

Make a periscope

Want to spy round corners without being seen?

You need a periscope!

What you need:

  • Cardboard
  • Duct tape
  • Scissors
  • Small mirrors

How to:

Ask an adult for help using scissors.

  1. Make a tall, rectangular tube out of your cardboard. The ends should be left open. Use one of the small mirrors to see how wide your tube needs to be. Use duct tape to secure your cardboard tube.
  2. Cut a flap on opposite ends and sides of your box. This flap should be the same height as your mirrors.
  3. Tape a mirror to the inside of each flap.
  4. Cut away the side of the cardboard opposite each flap.
  5. Angle both mirror flaps inward about 30 degrees. Look through the bottom of the periscope to see that what is seen on the top mirror is also reflected on the bottom mirror.
  6. Secure the mirror flaps with duct tape once you're happy with the angle.

Now you can look round corners and over walls! Is there a way to improve your periscope? Could you use a longer tube? How about camouflaging it?

What's happening?

When you look an object, you see it because the light from the sun or a lamp reflects off the object and goes into your eye.

If the object is round a corner, you can't see it anymore because the light reflecting off the object can't get into your eye. That's why you need a periscope.

A periscope uses mirrors to reflect the light from the object around the corner and into your eye.

Curriculum information