LEGO can be an essential tool in mechanical engineering as it is a form of what the field calls low-fidelity prototyping.
By using LEGO for prototyping, engineers and designers can quickly create and adjust models, making it ideal for initial concepts.
Patrick Faulkner, Lead Engineer at Accu, explains how LEGO can be a simple yet effective prototyping tool: “LEGO stands out as a low-fidelity prototyping tool because of its versatility, accessibility in education environments and ease of modification. LEGO engineering sets come with modular pieces that snap together seamlessly, letting designers experiment with structural layouts and simple design ideas, including mechanical functions, at minimal cost.
“When something doesn’t work, you can quickly disassemble and rebuild it, making iterations both fast and intuitive. This hands-on approach also helps you to spot potential design challenges early, well before moving on to more complex stages of product design and development.
“LEGO also has more advanced modules such as gears, hubs, axels, motors and even sensors. These can allow an even greater level of prototyping, allowing both physical and motion prototyping.”
A guide on how to use LEGO for prototyping
This guide mirrors how engineers use LEGO for prototyping, allowing children to explore the ideation and practical stages of engineering and building through play.
1. Start with a question
Begin by giving your child a simple challenge or question to guide their build. This helps them build with intention rather than just stacking bricks.
Examples might include:
• “Can you build something that moves?”
• “Can you make a bridge strong enough for your toy car?”
This helps children think with purpose and test ideas.
2. Add rules to the build (these are called design constraints)
Introduce a few gentle rules to shape the challenge. Engineers always work within limits, and children can learn to do the same through play.
For example:
• “It has to fit on this table.”
• “It must lift something small.”
This helps children plan ahead and understand real-world problem solving.
3. Choose a LEGO set that encourages engineering skills
Being intentional with the LEGO set you choose can make a big difference. Sets that include gears, wheels, axles, and beams encourage children to think about movement, mechanics, and structure rather than just appearance.
This helps children explore how parts connect, how movement is created, and the cause and effect.
4. Sort pieces together before building
Before building begins, encourage your child to group similar pieces together and lay them out so they can clearly see what’s available. This small step makes it easier to build, test, and adapt ideas.
This helps children learn organisational skills and develop independent thinking.
5. Start by building a strong base
Encourage your child to create a sturdy base or frame before adding any moving parts. A strong foundation helps everything else work more smoothly.
This helps children explore structural thinking and why things fall over.
6. Add one piece at a time and test often
Encourage your child to add just one gear, lever, or wheel at a time rather than all at once, and test it before moving on. This mirrors how real engineers check each part of a design as they build.
This helps children develop patience and logical thinking.
7. Encourage rebuilding and trying again
When something doesn’t work as expected, encourage your child to take apart only the most recent section and try a different approach. LEGO makes it easy to experiment without fear of getting it wrong.
This helps children explore problem solving, failure as a part of learning, and iteration.
8. Test the strength and stability of the structure
Once the build is complete, gently test it. Press lightly on the structure or place a small toy on top and observe what wobbles or stays firm.
This helps children understand weight, balance, support, and why engineers test designs before using them!
Ben Massey, MEng and customer success coordinator at health and safety software provider innDex, says that playing with LEGO also helps children develop health and safety awareness: “Using LEGO as a building tool taught me as a budding engineer about incidents and near misses in a controlled and playful environment. A collapsing LEGO tower becomes a physical metaphor for structural failure without any real danger, and it teaches you as a child to test different builds and be cautious of failure in the future. After all, health and safety is a number one priority in our industry.
“LEGO also makes it easier to see how infrastructure interacts with human behaviour. As a child, LEGO can be built as a group, encouraging teamwork and collaboration.”
Tech-enabled play isn’t the way to go
At CES 2026 in Las Vegas, LEGO Group announced the launch of LEGO SMART Play – tech-enabled LEGO that “brings play to life”.
LEGO SMART Play has three elements – the LEGO SMART Brick, LEGO SMART Tags, and LEGO SMART Minifigures. The LEGO SMART Tags and LEGO SMART Minifigures are paired with the LEGO SMART Brick to allow creations to become interactive in real time, responding to actions with relevant sounds and behaviours.
To make this possible, the LEGO SMART Brick is powered by a 4.1mm custom-made mixed-signal ASIC chip that measures smaller than a standard LEGO stud. It’s also packed full of accelerometers, light sensors, and a sound sensor as well as a miniature speaker driven by an onboard synthesiser.
However, the new platform has generated some concern that these ‘smart’ elements limit children’s imagination and creativity.
As Faulkner comments: “LEGO’s new SMART Play technology can make play more engaging, as long as it’s used to enhance creativity, not replace it. In my view, it works best as a layer added to traditional building, rather than a starting point.
“As an engineer, I know that playing with technology at a young age can do wonders for creativity and problem-solving, but only when it’s built on strong foundations. Before children introduce tech into their play, they need time to develop core skills such as structure, stability, and problem-solving through imagination alone. With LEGO, that means setting their own goals, adding simple rules to a build, and learning how to create sturdy bases through trial and error.
“Once those fundamentals are in place, Smart Play features can become a fun and meaningful addition. However, I wouldn’t recommend this kind of tech-led play for children under five. Around 90% of brain development occurs by that age, and those early years are best spent developing foundational, technology-free skills that help children get the most value from more advanced play later on.”
Future STEM careers
Engineering is now the second most sought-after career among children aged 13-16, according to the BBC Bitesize Careers survey. Other research has found that 78% of young people whose parents regularly take part in STEM activities with them express an interest in pursuing a career in engineering.
Taken together, these findings point to a connection between early experiences at home and the careers children go on to consider.
There is no doubt that LEGO can play a powerful role in inspiring the engineers of tomorrow, if used in the correct way. By mirroring real engineering processes, children can use their creativity to develop highly practical and problem-solving skills which will be essential in engineering and STEM careers.
