I held up a 3” by 5” index card and asked my kids, can you fit through this index card? It’s no surprise that they both giggled and said, “No!”

I told them it is possible, and I’ll show them how…all we need to do is make a few cuts with scissors to turn the index card into a connected chain that is large enough to fit through. Keep reading and I’ll teach you how to do this simple, exciting, and dare I say “magical” STEAM activity for kids.


  • 3” x 5” Index Card
  • Scissors


  1. Start by asking your kids if they think they can fit through an index card? Let them know it can be done and then ask how they think it could be possible. This is a great opportunity to let them practice engineering design/problem solving skills.

2. Optional: Use crayons, markers, or paint to color the index card on both sides. Let your kids use their imaginations and color it any way they like.  

3. Fold the index card in half, length-wise.

4. Starting on the folded side, use the scissors to make a cut on each end, about 1/4” from the end of the card and stopping about 1/2″ from the opposite side of the card.

1/4″ thick cut, stopping about 1/2″ from the opposite side of the card
Make this cut at each end of the card

5. Now, fill in-between the cuts made in step 4 by making the same ~1/4” thick cuts and stopping about 1/2″ from the opposite side of the card. Repeat this cut all the way across the card. 

6. Flip the card over and this time, starting on the unfolded end of the card, cut in-between each of the cuts make in Step 5. These cuts are also ~1/4” thick and stopping about 1/2″ from the opposite side of the card.

7. Cut through the loops made on the folded end of the card in Step 5, only cutting the interior loops and leaving the loops on both ends, created in Step 4, intact. 

Notice I’m starting with the second loop, leaving the first loop intact.

8. Open up the cut index card, it should make a large connected chain.

9. Ask your child to pull the chain over their head to see if they fit inside the index card. 

10. Your kids can now wear the index card chain as a necklace, waistband or anything they like. 

11. My son wanted to measure how long his index card chain was so we cut open the connected chain and stretched it out long ways on our table, comparing the length to our original index card. 


  • Math: The area of the index card is 3×5=15″. The perimeter of the index card is 3+3+5+5=16″. When we cut the card to make a long 1/4″ chain the area is still 15″: 1/4×60=15″. The perimeter is now changed 1/4+1/4+60+60=120.5″. So by cutting the chain we drastically increased the perimeter of the index card without changing the area. This is a great opportunity to teach kids about how to measure length and width, and the difference between the area of an object and the perimeter. Kids can also compare the length of the index card before and after it’s made into a chain. Ask them to figure out how many times longer the chain is than the original index card. 
  • STEM: In this activity kids are learning about how physical objects can change (in this case changing from 3”x5” rectangle into a long chain), and about the relative size of objects (the index card is small, but when cut into a chain it is large enough to fit through). Your kids may learn that the wider they make the cuts (larger than the 1/4” thick that I recommended), the smaller the final chain will be. This is because the width is increasing, but the length is decreasing. Kids are practicing following directions and fine motor (cutting with scissors) skills, both of which are important in STEM. They also can practice their engineering design/problem solving skills by figuring out how to make the index card into a chain on their own.
  • Art: Before cutting your kids can color the index card any way they like. Then the completed chain will be colorful and make a fun personalized necklace. 

Both my kids attempted this activity with me. The cuts to make the chain may seem complicated while you’re reading the instructions, but it is just many simple straight cuts, and is great scissor practice for kids. My 5 year old son was able to complete all the steps and make the index card chain himself. My 3 year old daughter had fun cutting with the scissors and made a smaller version of the chain (due to her wider cuts) with my help. 

Have you ever seen this activity done before? Are you going to “wow” your kids by teaching them how to turn an index card into a long connected chain? 


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