Here’s another easy STEM challenge coming your way! The classic Cup Tower Challenge is a quick STEM challenge that can be set up immediately and is excellent for elementary-age kids and older! Add in our free cup tower PDF printable, and you’re good to go with your engineering and math lesson today.


100 cup tower challenge with free PDF printablePin

What is the Cup Challenge?

The cup challenge is to build the tallest tower using 100 cups!

This specific STEM challenge can be completed in a short amount of time with younger kids, but you can also add layers of complexity to it for older kids. Add this one to your resource of awesome STEM activities, and you’ll always be prepared!

Many STEM projects use critical thinking skills as well as math and engineering skills, and this one is no exception. Attention to detail is a must, and pre-planning is encouraged! This can be timed or not timed.

Additionally, if you have the time, add in a design and planning stage and a conclusion stage where everyone shares what worked and what didn’t. See our STEM reflection questions.

Ask a few questions:

  • What factors contribute to one tower being taller than the other?
  • What was the most challenging thing about this STEM project?
  • What would you do differently if you could try it again?
  • What worked well and what didn’t work well during the challenge?

How Many Cups Do You Need to Make a Tower?

100 cups is often chosen as an easy way to prep this activity for a group of kids. It provides a limit so that kids can exercise their creativity and ingenuity.

However, in all honesty, it doesn’t need to be 100 cups! Whatever you have is fine. You know, the ones left over from birthdays or that last family party. If you need to buy a bag, that’s ok too. There are plenty of ways to do this challenge and reuse the cups!

Nerf and cups are great too! We had friends over, and I set up these tower challenge cups all around the house for targets! Or how about catapult targets? There are so many possibilities…

Use more cups to make your tower if you want to challenge your kids. Ask the kiddos how tall they want to build it and see if they can do it! Or use less if you are doing this activity with younger kids, or you are short on time.

TIP: Although this is a one-supply challenge, you can add items such as index cards and popsicle/craft sticks to it for added challenges like we did here.

For more fun cup tower ideas check out…

STEM Challenge Supplies

This is one of my favorite STEM building challenges because it’s so inexpensive to set up and uses just one type of supply – cups. See here for more cheap STEM supplies.

The FREE printable STEM pack below is also a great way to introduce even more low-cost STEM activities into the mix that kids of all ages can tackle. It will definitely keep them busy!

Click here to get your 100 Cup Tower Challenge Sheet.


Cup Tower Challenge Ideas

Let’s get started! Use this STEM activity as a fantastic way to start the day or as a way to end the day. Either way, kids have a lot of fun with it!

CUP TOWER CHALLENGE #1: Who can make the tallest cup tower (it doesn’t have to be 100)?

CUP TOWER CHALLENGE #2: Who can make the tallest 100-cup tower?

CUP TOWER CHALLENGE #3: Can you build a tower as tall as you or as tall as the door frame?

TIME NEEDED: At least 15-20 minutes is usually a good time allotment if you need to keep track of the clock, but it can also become an open-ended activity that can morph into new challenges.


  • Cups (100 if possible)
  • Index cards, craft sticks, cardboard (optional)
  • Printable Sheets


Another thing I love about this quick STEM activity is the setup time! The supplies are easy to grab so you can try this STEM project right away.

If you need to go and get cups, try this PAPER CHAIN STEM CHALLENGE in the meantime.

STEP 1: Give out supplies. For example, set a bag of cups on the counter! It’s that easy!

STEP 2: Give a minute or two for a planning phase (optional).

STEP 3: Set a time limit (15-20 minutes is ideal). This is also optional.

STEP 4: Once the time is up, have the kids measure the tower(s).


Hint: Incorporate extra math in this step!

  • Grab a measuring tape to measure and record each tower.
  • If more than one tower is made, compare the heights of the towers.
  • If the challenge was to make a tower as tall as the door or the kiddo, how many cups did it take?
  • Count to 100 as you pick up the cups, or use the Nerf guns to take down the towers first and then count to 100 or whatever number!

STEP 5: If it works for you, have each kiddo share his/her thoughts on the challenge. A good engineer or scientist always shares his/her findings or results.

STEP 6: Have fun!


More Quick and Easy STEM Challenges

Straw Boats Challenge – Design a boat made from straws and tape, and see how many items it can hold before it sinks.

Strong Spaghetti – Get out the pasta and test our your spaghetti bridge designs. Which one will hold the most weight?

Paper Bridges – Similar to our strong spaghetti challenge. Design a paper bridge with folded paper. Which one will hold the most coins?

Paper Chain STEM Challenge – One of the simplest STEM challenges ever!

Egg Drop Challenge – Create your own designs to protect your egg from breaking when it is dropped from a height. 

Strong Paper – Experiment with folding paper in different ways to test its strength and learn what shapes make the strongest structures.

Marshmallow Toothpick Tower – Build the tallest tower using only marshmallows and toothpicks.

Penny Boat Challenge – Design a simple tin foil boat, and see how many pennies it can hold before it sinks.

Gumdrop Bridge – Build a bridge from gumdrops and toothpicks and see how much weight it can hold.

Spaghetti Marshmallow Tower – Build the tallest spaghetti tower that can hold the weight of a jumbo marshmallow.

Paper Clip Challenge – Grab a bunch of paper clips and make a chain. Are paper clips strong enough to hold weight?

More Engineering Resources

Below, you’ll find various engineering resources to supplement the many engineering projects on the website. From the design process to fun books to key vocabulary terms, you can feel confident providing these valuable skills. Each one of the resources below has a free printable!


Engineers often follow a design process. There are many different design processes that all engineers use, but each one includes the same basic steps to identify and solve problems.

An example of the process is “ask, imagine, plan, create, and improve.” This process is flexible and may be completed in any order. Learn more about the Engineering Design Process.


Is a scientist an engineer? Is an engineer a scientist? It might not be very clear! Often, scientists and engineers work together to solve a problem. You may find it hard to understand how they are similar yet different. Learn more about what an engineer is.


Sometimes the best way to introduce STEM is through a colorfully illustrated book with characters your kids can relate to! Check out this fantastic list of teacher-approved engineering books, and get ready to spark curiosity and exploration!


Think like an engineer! Talk like an engineer! Act like an engineer! Get kids started with a vocabulary list that introduces some awesome engineering terms. Make sure to include them in your next engineering challenge or project.


Use these reflection questions below with your kids after they have completed a STEM challenge. These questions will encourage discussion of the results and increase critical thinking skills. These questions or prompts will help to promote meaningful discussions individually and in groups. Read the questions for reflection here.

Click on the image below or the link for more engineering activities for kids.

Printable STEM Pack for Kids

80+ Doable Engineering Projects in one convenient pack!

  • Full instructions with sample images
  • Activity-specific instruction sheets
  • Data Collection Sheets
  • Questions for Reflection
  • Architecture Building Cards: Try the tallest tower challenge
  • Bridge Building Cards: Explore different types of bridges to build your own.
  • Paper Chain STEM Challenge: Who can make the longest chain? Great icebreaker or quick challenge!
  • 3 Little Pigs Architectural Pack: Design a house that won’t blow away!
  • Great marshmallow challenge: A classic challenge kids love!
  • Real-world STEM challenge lesson but don’t know where to start? Our easy-to-follow template shows the steps!
  • What’s the difference between a scientist and an engineer?
  • Crossword and word search with engineering vocabulary.
  • Engineering vocabulary cards
  • Design a one-of-a-kind invention and write about it with this 5-page activity!