The design cycle

Most school engineering follows a simple loop: understand the problem, imagine possible solutions, plan one, build it, test it and improve it. The loop matters more than the finished product. A bridge that collapses on the first test and holds on the third has taught more than one that works first time by luck.

Constraints make the task meaningful. A limited number of materials, a set budget in pretend currency or a size limit forces pupils to make choices and explain them.

A sample challenge: the paper bridge

This suits pupils aged 9 to 13 over two 45-minute lessons. Each group of three needs ten sheets of A4 paper, a metre of masking tape, two stacks of books set 25 cm apart and a supply of coins or washers to use as weights.

• Set the task: build a bridge that spans the gap and holds as many coins as possible.

• Give groups ten minutes to sketch two ideas before they touch any materials.

• Build and test the first design, recording the load at which it fails.

• Look at other groups' bridges and note one idea worth borrowing.

• Rebuild with the same materials and test again, then explain what changed.

Materials and kits

Cardboard, tape, string and recycled packaging cover a great deal of early engineering. As pupils get older, construction and robotics kits such as LEGO Education sets or micro:bit add-on boards bring in motors and sensors, which link engineering to programming.

Kits are useful, but they can narrow thinking if every task has a set answer. Mixing open-ended challenges with kit-based ones keeps pupils designing rather than only following instructions.

Real contexts help pupils see the point of the work. A task framed around a need in the school, such as a shelter for the bike rack or a better way to carry trays, gives a clear user to design for and a reason to ask that user what they want before building anything.

Assessing the process

Marking only the final product rewards luck and confident builders. A short design log, with a sketch, a test result and a sentence on what was changed, gives teachers evidence of reasoning. It also gives quieter pupils a way to show their thinking.

School leaders can support this by giving engineering tasks enough time. A challenge squeezed into one lesson rarely reaches the improve stage, which is where most of the learning happens.

Key points

• Use clear constraints so pupils have to make design choices.

• Always leave time for a second build after testing.

• Assess the design log, not just the finished model.

• Balance kit-based tasks with open-ended challenges.

Photos: Kevin Jarrett, Green Liu / Unsplash