The last few weeks of school are a special kind of chaos. Students are restless, routines are slipping, and keeping engagement high feels like a full-time job on top of your actual full-time job.
But here’s the thing, this is actually the perfect time for STEM challenges.
Low prep, high engagement, and genuinely fun?
Yes, please.
These five end of year STEM challenges will keep your students thinking, building, collaborating, and laughing all the way to the final bell, without adding more to your already-full plate. And because every challenge includes a built-in SEL mini-lesson, students aren’t just building structures, they’re building skills.
Why STEM Challenges Work at the End of the Year
When students are checked out, worksheets don’t stand a chance. But give them something to build? They’re in.
STEM challenges tap into the engineering design process, students plan, build, test, and improve. That kind of hands-on learning keeps even the most distracted end-of-year brain engaged. And because most of these challenges use simple, low-cost materials, there’s no scrambling for supplies or busting your budget in June.
What sets these challenges apart is that each one includes an SEL mini-lesson built right in. Before students build, they set an intention. While they build, they practice it. After they build, they reflect on it. That structure is what turns a fun activity into a meaningful learning experience.
1. Frog Catapult STEM Challenge 🐸
The challenge: Build a catapult that launches a frog (or small object) as far, or as accurately, as possible.
Students love anything that involves launching things across the room, and this challenge delivers. They’ll explore physics concepts like force, distance, and trajectory while using the engineering design process to test and improve their designs.
It’s one of those challenges where you’ll hear genuine excitement, the kind that reminds you why you became a teacher in the first place.
Materials: craft sticks, rubber bands, plastic spoon, small object to launch Time: 45–60 minutes Skills: engineering design, measurement, force and motion, perseverance, managing frustration
➡️ Leap Frog Catapult STEM Challenge
2. Greenhouse Build Challenge 🌿
The challenge: Design and build a greenhouse structure that can protect a plant (or small object) inside.
This one naturally connects to end-of-year science content around plants, ecosystems, and life cycles. Students work through the design process, planning their structure, choosing materials, building, and testing whether their greenhouse actually does its job.
It’s a great way to tie up science content with a hands-on engineering experience, and the results are surprisingly creative.
Materials: craft sticks, plastic wrap, tape, cardboard, popsicle sticks Time: 45–60 minutes Skills: engineering design, structures, plant science connections, growth mindset
➡️ Greenhouse Build STEM Challenge
3. Paper Chain STEM Challenge 📎
The challenge: Using only two pieces of paper and 12 inches of tape, build the longest paper chain possible.
Don’t let the simplicity fool you. This challenge is deceptively engaging. Students quickly realize there’s more strategy involved than they expected, how they cut, fold, and connect each link makes a huge difference in the final length.
It’s also one of the easiest challenges to run when you’re short on time or supplies, which makes it a reliable go-to for those final hectic weeks.
Materials: 2 pieces of paper, 12 inches of tape, scissors, ruler Time: 30–45 minutes Skills: engineering design, measurement, problem-solving, teamwork
Already love paper STEM challenges? Check out my post on 5 Paper STEM Challenges Your Students Will Love for more ideas that use materials you already have on hand.
4. Straw Tower Challenge 🏗️
The challenge: Using only straws and tape, build the tallest OR strongest (teams can choose their goal) freestanding tower possible.
A classic for good reason. The Straw Tower Challenge never gets old because there’s always a new strategy to try, and students are endlessly motivated by the competitive element of building taller or stronger.
This one is also fantastic for talking about structural engineering, why do some designs hold up while others collapse? What makes a structure stable? The debrief conversations are as valuable as the build itself.
Materials: straws, tape, ruler Time: 45–60 minutes Skills: engineering design, structures, measurement, problem-solving, communication, teamwork
5. Gratitude Bridge Challenge 🌉
The challenge: Design and build a bridge, then use it as a launching point for a meaningful SEL reflection on the people, moments, and experiences that “carried” students through the year.
This is my favorite challenge to save for last, and not just because it’s a great STEM build. The Gratitude Bridge combines structural engineering with social-emotional learning in a way that gives the end of the year real meaning.
Students build a bridge that can hold weight, then reflect on what has supported them, their classmates, their teachers, their own growth. It’s a powerful, memorable way to close out the school year, and one that students genuinely remember.
Want more ideas for weaving SEL into your STEM challenges? Read SEL in STEM: 5 Ways to Add Social-Emotional Learning to Any STEM Challenge for simple strategies you can use right away.
Materials: index cards, tape, craft sticks, string, clothespins or paper clips Time: 60 minutes Skills: engineering design, structures, SEL reflection, gratitude
➡️ Gratitude Bridge STEM + SEL Challenge
Tips for Running These Challenges in the Last Weeks of School
Keep groups small. Pairs or groups of three work best when energy is high and patience is low. Smaller groups mean more hands on the build and fewer arguments about whose idea to use.
Use the engineering design process every time. Even at the end of the year, especially at the end of the year, walking students through plan, build, test, and improve keeps the challenge structured and purposeful. It’s a great habit to reinforce before summer.
Celebrate the process, not just the winner. Acknowledge the teams who iterated the most, who supported each other best, or who came up with the most creative design. This is especially meaningful paired with the Gratitude Bridge challenge.
Let students lead the debrief. Ask them: What worked? What would you change? What did you learn about working with your team? Their answers will surprise you.
Grab All 5 Challenges
Want all five of these ready-to-go with student recording journals, challenge slides, SEL mini-lesson, self-assessments, and teacher instructions?
Each challenge is available individually in my TPT store:
- 🐸 Frog Catapult STEM Challenge with SEL mini-lesson (add link)
- 🌿 Greenhouse Build STEM Challenge with SEL mini-lesson (add link)
- 📎 Paper Chain STEM Challenge with SEL mini-lesson (add link)
- 🏗️ Straw Tower Challenge with SEL mini-lesson (add link)
- 🌉 Gratitude Bridge STEM with SEL mini-lesson (add link)
Looking for more low-prep STEM ideas? Browse all my STEM + SEL Challenges or follow along on Instagram for quick tips and new ideas every week.
