30 STEM challenges by grade
A STEM challenge gives a small team a problem, a short list of cheap materials and a time limit, then tests every design the same way. Ten challenges for each grade band, K–2, 3–5 and 6–8, using paper, tape, cups, craft sticks and recycling. None needs heat or a sharp tool in a student's hands; where something must be cut, you cut it beforehand.
Kindergarten to 2nd grade
1. Tallest cup tower
Teams build the tallest tower they can from ten paper cups in five minutes. It has to stand on its own while you count to five. Measure with a tape measure or in hand spans.
Grades K–2You need Ten paper cups per teamUse 5 minute timer
2. Bridge for a toy car
Set two books a ruler's length apart. Teams build a bridge from blocks that the toy car can roll across without the bridge falling down.
Grades K–2You need Building blocks, two books and a small toy car
3. Foil boat with coins
Each team shapes one square of foil into a boat, then adds coins one at a time until it sinks. Count the coins it held before it went under.
Grades K–2You need A square of foil per team, a tub of water and coins
4. Longest paper chain
From one sheet of paper, teams make the longest paper chain they can in ten minutes. Lay the chains side by side to compare.
Grades 1–2You need One sheet of paper, safety scissors and a glue stick per team
5. A house that survives the wind
Teams build a small house from craft sticks and play dough. Test it by fanning it three times with a folded paper fan; it should stay standing.
Grades K–2You need Craft sticks, play dough and a paper fan
6. Sink or float
Students predict whether each object will sink or float, sort the objects onto two sheets, then test each one and move any they got wrong.
Grades Pre-K–1You need A tub of water and ten small classroom objects
7. Ramp roll
Roll three balls down the same book ramp and measure how far each goes in paper clip lengths. Ask which went farthest and why they think so.
Grades K–2You need A book ramp, three different balls and paper clips
8. Build a nest
Teams build a nest from natural and scrap materials that holds a pom-pom egg when you tip it gently. Test each nest the same way.
Grades K–2You need Twigs, grass, string, paper strips and a small pom-pom
9. Shadow puppet theater
Teams make two shadow puppets and find out how to make the shadow bigger and smaller by moving the puppet toward and away from the light.
Grades 1–2You need Card shapes on craft sticks and a flashlight
10. Strongest paper column
Fold paper into three columns: a triangle, a square and a circle. Stack books on each one at a time and count how many books each column holds.
Grades 1–2You need Paper, tape and a stack of picture books
3rd to 5th grade
11. Newspaper tower
Teams build the tallest freestanding tower they can from ten sheets of newspaper and the tape in fifteen minutes. Measure each tower and record the heights on a bar graph.
Grades 3–5You need Ten sheets of newspaper and a meter of masking tape per teamUse Bar graph template, 15 minute timer
12. Slowest parachute
Teams make a parachute that lowers a small toy figure as slowly as possible from the same height. Time each drop with the stopwatch and test three times.
Grades 3–5You need Plastic bags, string, tape and a small toy figureUse Stopwatch
13. Paper airplane distance
Each student folds three airplane designs and throws each one three times from the same line. They measure, find the average distance, and pick the best design.
Grades 3–5You need Paper and a tape measureUse Bar graph template
14. Index card bridge
Teams build a bridge from ten index cards and tape across a gap between two desks, then add coins to the middle until it fails. Record how many it held.
Grades 3–5You need Ten index cards, tape and coins
15. Balloon rocket
Tape a blown-up balloon to a straw threaded on a string and let it go. Teams change one thing at a time, such as balloon size, and measure the distance. Check for latex allergies first.
Grades 3–5You need A balloon, a straw, string across the room and tape
16. Marble run on the wall
Teams tape tube halves to a wall to make a marble run that takes as long as possible to reach the bottom. Time each run with the stopwatch.
Grades 3–5You need Paper towel tubes cut in half by you, painter's tape and a marbleUse Stopwatch
17. Craft stick catapult
Teams build a catapult that launches a pom-pom into a cup set on the floor two meters away. Agree the rule first: aim only at the target, never at people.
Grades 3–5You need Craft sticks, rubber bands, a plastic spoon and pom-poms
18. Water filter
Teams layer sand, gravel and cotton in the upside-down bottle top and pour muddy water through. Compare how clear each team's water is. Nobody drinks the water.
Grades 4–5You need A plastic bottle you have cut in half, sand, gravel, cotton balls and muddy water
19. Keep the ice cube
Teams wrap an ice cube to keep it from melting as long as possible. Check every ten minutes and record which design lasted longest.
Grades 3–5You need Ice cubes, small cups and scrap materials like foil, fabric and paper
20. Paper helicopter
Students fold a paper helicopter that spins as it falls, then change the wing length and time how long it takes to land from the same height.
Grades 3–5You need Paper strips, safety scissors and paper clipsUse Stopwatch
6th to 8th grade
21. Shake-table tower
Teams build a tower on the tray, then shake the tray side to side for ten seconds. The tallest tower still standing wins. Teams improve the design and test again.
Grades 6–8You need Craft sticks, binder clips and a baking tray on two round pencils
22. Cardboard stool
Teams design a stool from cardboard panels and tape that holds a stack of textbooks without bending. Sketch the design first, then build and test with books added one at a time.
Grades 6–8You need Flat cardboard you have pre-cut into panels, and tape
23. Marble roller coaster with a loop
Teams build a roller coaster that sends a marble through one loop and stops it at the end. They find the lowest starting height that still gets the marble through the loop.
Grades 6–8You need Foam pipe insulation cut in half by you, tape and marbles
24. Pulley lift
Teams build a pulley with spools on a pencil axle that lifts a cup of coins from the floor to the desk. Compare how hard it is to pull with one pulley and with two.
Grades 6–8You need Empty thread spools, a pencil, string and a cup of coins
25. Straw rocket
Students roll a paper rocket around a pencil, add a nose cone and fins, and launch it by blowing through a straw. Test fin designs and measure the distance of three launches each.
Grades 6–8You need Paper, tape and drinking straws
26. Craft stick bridge
Teams glue a bridge from twenty craft sticks to span a gap the length of a ruler, let it dry overnight, then load it with books until it bends. Use white glue only, never hot glue.
Grades 6–8You need Twenty craft sticks and white glue per team
27. Zip line carrier
Teams build a carrier that takes a small toy down a sloped string as slowly as possible without stopping. Time each run with the stopwatch.
Grades 6–8You need String stretched across the room, paper cups, paper clips and a small toyUse Stopwatch
28. Packaging challenge
Teams fold one sheet of cardstock into a box that holds as many dried beans as possible. They sketch the net on graph paper first and compare volume to the cardstock they used.
Grades 6–8You need One sheet of cardstock per team, tape and dried beansUse Centimeter graph paper
29. Clay boat
A ball of clay sinks. Teams reshape the same lump into a boat that floats, then load it with coins and explain why the new shape floats.
Grades 6–8You need A small lump of modeling clay per team, a tub of water and coins
30. Model hand
Teams build a model hand with straw finger joints and strings for tendons. The hand should pick up a paper cup when the strings are pulled.
Grades 6–8You need Drinking straws, string, tape and cardboard
Making it work
- Use the same test for every team, and announce it before building starts, so the result feels fair.
- Set a visible time limit with the timer; most challenges need ten to twenty minutes of building.
- Make teams of three or four with the random group maker, and give each person a role: builder, materials, timekeeper, recorder.
- Ask for a sketch before building in grades 3 and up, and a short written "what we'd change" afterward.
- Do any cutting with a craft knife or sharp scissors yourself before the lesson. Students use safety scissors only, and nothing hot.
Questions teachers ask
- What does STEM stand for?
- Science, technology, engineering and math. A STEM challenge is usually an engineering task: a problem, limited materials and a fair test, with science and math used to explain and measure the result.
- How do I run a STEM challenge with a big class?
- Teams of three or four, all materials in one bag per team, a strict time limit and one test station you run. Everyone gathers to watch each test, which keeps the room calm.
- What materials should I keep for STEM challenges?
- Paper cups, craft sticks, masking tape, string, index cards, paper clips, foil, rubber bands and clean recycling such as tubes and boxes. Ask families to send clean recycling at the start of the year.
- What if a team's design fails?
- That is part of the work. Ask the team what they think went wrong and what they would change, then give five minutes to rebuild and test again if time allows.
Written for teachers by Peabody Teach. No ads, no affiliate links. Something wrong or missing? Tell us.