When the kids and I were in the middle of our pirate unit, we discussed how pirates often used telescopes to help them see far into the distance. We decided to build our own fully functioning telescope so we could be just like pirates! Read on to learn how to make a telescope that your kids can use and enjoy.
Note: For more kid-friendly science activities, see my Science Activities for Kids page.
I purchased a build-your-own-telescope kit from RAFT, which is a great organization that upcycles discarded materials into educational activities. (If you can’t find a telescope kit from RAFT, you can check out this basic one and this more advanced one available on Amazon. Both of these kits seem like they would be fairly inexpensive ways to show kids how to make a telescope.)
This picture shows the contents of our kit, which included:
- an outer tube (the green one)
- an inner tube (the black one)
- A convex lens
- A concave lens
- A red lens cap to hold the convex lens in place
- A cloth to clean the lenses
QBoy helped me to assemble the kit by placing the large, convex lens in the green tube. He secured it in place with the red lens cap.
Then I let him experiment a bit to see what the convex lens did. He noticed that things looked a bit larger when viewing them through the convex lens.
Then we inserted the concave lens into the end of the black tube.
Again, I let QBoy play a bit. He observed that things looked a bit smaller when viewing them through the concave lens.
We then assembled our telescope by inserting the black tube with the concave lens into the green tube with the convex lens.
At this point, I asked QBoy what he thought would happen when we combined the two lenses together. He made a very reasonable prediction that things would look medium (since one lens made things look bigger and one lens made things look smaller).
At this point, I handed him the telescope and let him adjust it so he could focus on a distant target. Somewhat to his surprise, things did not look medium. Instead, using the telescope made things look much bigger!
I left the telescope on our shelves for a few weeks, as the kids would often pick it up and wander around the house looking at things with it. It was great practice for them to have to adjust the telescope to look at objects at varying distances.
Plus, we learned that the key to making a telescope is to combine a concave with a convex lens in order to magnify what we are seeing. Science lesson learned!
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