Engineering is fundamentally about solving problems—identifying needs, generating ideas, testing solutions, and improving designs. When children engage in engineering challenges, they develop skills that extend far beyond building. They learn to think systematically, embrace failure as feedback, and persist through difficulties. These challenges use simple materials to pose genuine engineering problems that engage children while teaching them to think like engineers.
The Engineering Design Process
Before presenting challenges, teach children a simplified version of the engineering design process. This framework guides their thinking and helps them approach problems systematically.
- Ask: What is the problem? What are the constraints and criteria for success?
- Imagine: What solutions might work? Brainstorm multiple ideas without judging them yet.
- Plan: Choose one idea and sketch it out. List the materials and steps needed.
- Create: Build your solution. Follow your plan but adapt as you learn.
- Test: Does it meet the criteria? Measure and evaluate honestly.
- Improve: Based on testing, how can you make it better? Iterate and retest.
Real engineers rarely succeed on their first attempt. Emphasise that iteration is normal and valuable. Each "failure" provides information that improves the next design. Celebrate the learning process, not just successful outcomes.
Challenges for Younger Children (Ages 5-8)
Paper Aeroplane Distance Challenge
The challenge: Design and fold a paper aeroplane that flies the farthest distance.
Materials: A4 paper, measuring tape, masking tape to mark distances
Engineering concepts: Aerodynamics, lift, drag, testing and iteration
Start with a basic design and measure how far it flies. Then, systematically change one element at a time: wing size, nose weight (add a small paper clip), wing shape. Record distances for each modification. Which changes improved performance? Why might that be?
Extension: Set additional criteria—the plane must fly straight, or must stay airborne for the longest time (different from distance).
Tallest Tower Challenge
The challenge: Build the tallest free-standing tower using only 30 pieces of dried spaghetti and 20 mini marshmallows.
Materials: Spaghetti, marshmallows (or blu-tack), ruler
Engineering concepts: Structural stability, triangular bracing, load distribution
Children quickly discover that height without stability leads to collapse. Successful designs typically incorporate triangular shapes, which are inherently stable. Discuss why triangles work better than squares for structural support.
Egg Protection Drop
The challenge: Design a container that protects a raw egg when dropped from increasing heights.
Materials: Cardboard, newspaper, cotton balls, tape, rubber bands, straws, string
Engineering concepts: Impact absorption, energy dissipation, protective design
Start drops from a low height (1 metre) and increase gradually. This allows designs to succeed at early stages before facing greater challenges. Discuss how professional engineers test products—starting with easier conditions before extreme testing.
Challenges for Middle Years (Ages 9-11)
Bridge Building
The challenge: Build a bridge that spans 30 centimetres between two supports and holds the most weight.
Materials: 50 paddle pop sticks, PVA glue, string (optional)
Engineering concepts: Tension, compression, beam vs. arch design, load distribution
Allow time for glue to dry between building sessions. Test bridges by gradually adding weight (coins, washers, or small weights) until failure. Document how much weight each design held and observe where failure occurred. Discuss how this information could improve the next design.
For groups, add a budget constraint: each material has a "cost," and teams must build within a budget. This adds project management to the engineering challenge and reflects real-world constraints.
Catapult Design
The challenge: Build a catapult that launches a marshmallow to hit a target at a set distance.
Materials: Paddle pop sticks, rubber bands, plastic spoons, small cups
Engineering concepts: Potential and kinetic energy, trajectory, force, accuracy vs. power
After building, run accuracy tests: Can you consistently hit a target? Adjust the design to improve accuracy. Then try power tests: How far can your catapult launch? Children discover that accuracy and maximum distance often require different design choices.
Boat Racing
The challenge: Design a boat that crosses a water-filled container in the fastest time, powered only by a small fan (same for all competitors).
Materials: Aluminium foil, straws, paper, tape, styrofoam
Engineering concepts: Buoyancy, drag, sail design, hull shape
This challenge involves multiple engineering sub-problems: the boat must float (buoyancy), move efficiently through water (hull design), and catch wind effectively (sail design). Iteration typically improves performance dramatically.
Advanced Challenges (Ages 12+)
Rube Goldberg Machine
The challenge: Create a chain reaction machine that performs a simple task (like ringing a bell) using at least 10 steps.
Materials: Household items: dominoes, marbles, cardboard tubes, ramps, string, cups
Engineering concepts: Energy transfer, cause and effect, sequencing, reliability
This extended project teaches patience and systematic debugging. When a step fails, engineers must diagnose why and improve that specific element without disrupting the rest of the chain. The challenge is in reliability—can the machine work consistently?
Wind-Powered Vehicle
The challenge: Build a vehicle powered by wind (from a fan) that travels the greatest distance.
Materials: Cardboard, straws, wooden skewers, bottle caps (wheels), paper or fabric (sail)
Engineering concepts: Force, friction, wheel and axle mechanics, sail efficiency
Variables to optimise include wheel size and material (affecting friction), sail size and shape (affecting force capture), and overall weight (affecting inertia). Systematic testing of each variable teaches experimental methodology alongside engineering.
🔧 Challenge Design Principles
- Clear, measurable success criteria (distance, weight held, time)
- Constraints that require creativity (limited materials, budget, time)
- Multiple valid solutions (no single "right answer")
- Opportunity for iteration and improvement
- Connections to real-world engineering applications
Facilitating Engineering Challenges
Your role as a facilitator is crucial but should be hands-off. Resist the urge to fix problems for children or suggest solutions. Instead, ask guiding questions:
- "What did you notice when that happened?"
- "What do you think caused it to fail at that point?"
- "What could you change to make it stronger/faster/more stable?"
- "Have you seen anything similar that works well? What could you learn from it?"
If children become frustrated, acknowledge the challenge while expressing confidence in their ability to solve it. "This is a hard problem—that's what makes it interesting. Take a break and come back with fresh eyes."
Connecting to Real Engineering
Help children see connections between their challenges and real-world engineering:
- Paper aeroplanes connect to aircraft design and aeronautical engineering
- Tower building relates to structural engineering and architecture
- Egg drops connect to packaging design and safety engineering
- Bridge building relates to civil engineering
- Catapults connect to mechanical engineering and physics
Share stories of famous engineering achievements and failures. The iterative process children experience mirrors how real engineers work—the Mars rovers were tested extensively, bridges are designed with careful analysis, and even simple products go through multiple prototypes.
Assessment Without Grades
Focus reflection on process rather than just outcomes. After each challenge, discuss:
- What worked well in your design?
- What would you do differently next time?
- What did you learn that surprised you?
- How did you feel when something did not work? How did you respond?
This reflection builds metacognition—awareness of one's own thinking and learning processes—which supports all future learning.
Engineering challenges pair well with other STEM activities. Try combining building with coding by adding programmable elements, or connect to mathematics by calculating forces, distances, and ratios in your designs.