STEM challenges for kids are an easy way to work science, technology, engineering and mathematic principles into play. Today we are doing a red cup challenge that is one of our favorite STEM activities. In the red cup STEM challenge, kids will explore STEM planning, experimenting and implementation all within the framework of a fun game.

red cup stem challenge idea for kids shown with child lifting a red cup from a pyramid with a straw - text: stack the cups without touching them - Kids Activities Blog
Let’s use red cups in a easy to set up STEM challenge for kids!

STEM Challenges for Kids

Do you ever have an “Ah-ha” moment? When a new STEM concept becomes obvious to kids, it can be exciting! Encourage learning through STEM activities by hosting your own STEM challenge! A STEM challenge can be independent study with one student challenging time, distance or height, or with multiple students including a whole classroom competing against each other.

Related: More STEM challenges for kids: Building with Straws & Cargo Flying

Implementing the STEM Red Cup Challenge in the Classroom

About two years ago I started teaching an integrated science course. The Integrated Science Class is a large class of 39 kids, with mixed grades (3rd to 8th graders) and we strive to mix science, technology, engineering and math skills each week, learning by solving challenges.  

Every week we break the kids up into teams randomly and give them a set of rules for their new STEM challenge. The red cup STEM challenge worked really well with a large group – this is how we implemented it in the classroom.

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how to host a red cup stem challenges for kids  - image shows a LEGO minifigure on the top of a pyramid of red cups from the challenge with several children near by - Kids Activities Blog
Here is how to host a STEM challenge for kids.

STEM Red Cup Stacking Challenge for Kids

1. Break Into Teams for Red Cup Challenge

At the beginning of the class we broke the kids into teams. We typically run 35-40 kids a class period, breaking into teams makes the class more manageable. The teams are completely random, and each week the kids are paired with a new group and new challenges. 

2. Each Team Receives the Same Supplies for STEM Challenge

In our red cup challenge, each team received these supplies. You can alter the number and type of supplies based on time and number of kids in the class.

STEM Cup Tower Supplies for each team

Directions for red cup challenge - plastic cup stem challenge - image shows pyramid of red cups with children's hands holding rubber bands lifting the cups
How creative can you get when building without touching the cups?

Cup Tower Directions

Our directions for the red cup challenge were intentionally brief and open-ended…

Goal of Cup Stacking Challenge:

The ultimate goal of the red cup STEM challenge was that teams needed to make a pyramid of red cups and place a LEGO minifigure on the top of the tower WITHOUT TOUCHING THE CUPS OR THE FIGURE WITH THEIR HANDS.

Finished red cup stem challenge for kids - Stem games for kids - finished red cup pyramid shown with minifigure successfully on top - Kids Activities Blog
We won the red cup challenge!

Working together to complete the Cup Challenges

The kids need to work together to come up with a way to move the cups. There were several good (and different) techniques experimented with in our classroom:

  • Some kids lifted the cups with the straws.
  • Other children tried tying the string to the cups and then lifting the string ends to lift the cups.  
  • Another team stretched rubber bands to place them around the cups, then lifted the cups as a team. 

Winning the Cup Stacking Challenge

After a team “won” the challenge, I would ask them to tell me to show me how they did it… and then we would remove a tool or add an obstacle and they had to re-think the challenge and re-do it. 

new obstacle for the stem challenge with plastic cup - child shown blindfolded and doing the red cup challenge
Do you need another obstacle for the challenge?

The STEM Cup Challenges Didn’t Stop There!

Some of the additional challenges and obstacles we placed on teams for the second round:

  • For the team that lifted the cups with the straws we took the straws away.
  • For a team that had struggles communicating we made everyone silent except for the child who was the quietest.
  • For a team who was super, super fast, we had them put their left hands into their back pockets.
  • Another team had half of their members blind-folded with crepe paper blindfolds.

STEM Cup Stacking Game FAQ

What is the cup stacking game called?

Describing the red cup stacking game are many names like Solo cup stacking, cup engineering challenge, Solo cup challenge, Stack attack and just plain old cup stacking!

How many cups do you need for cup stacking game?

For our Solo Cup stacking challenge, we used 10 cups so a four high pyramid could be formed. If you are playing with adults or older kids giving them a higher pyramid could be a fun challenge like 15 cups or 21 red cups.

What is a STEM Challenge? What makes a good STEM challenge?

We love a good STEM challenge because it is an open-ended learning experience for the participants to use science, technology, engineering and mathematic knowledge in a hands on way. In my opinion, a good STEM challenge is simple, uses common items and has a hint of competition!

How do you stack cups without touching them?

The question of how to stack cups without touching them could be answered a million ways! But the common solutions in our experience is to use something in between the hands and the cup like straws, string or rubber bands.

text: build with straws STEM challenge - two images showing childrens hands manipulating straws for building within the STEM challenge - Kids Activities Blog
Let’s do another STEM challenge!

More STEM Activities for Kids

In Case You Need More Fun Ideas:

What did your kids think about the red cup STEM challenge? How did they solve the building problems?

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  1. This cup stacking challenge looks so fun! I’m always looking for engaging activities to do when I babysit, I’ll have to get some cups to try this out.

  2. I am all for any type of educational activity that we can do with things we already have at home, like this fun cup challenge!

  3. It’s always a blast watching a group work through a cup challenge…and these variations definitely take it up a notch!

  4. We homeschool but my kids had a lot of fun with this. The cup stacking challenge was something they could do together even though they are in different grades.

  5. Love the simplicity of this cup challenge. The kids had so much fun stacking cups and trying to negotiate the obstacles.