How to build a stable LEGO Bridge

Are you ready for our 6th LEGO activity for the summer? We made several bridges and devised a way to test how stable they were.

First we discussed how to test each bridge, we tried adding weights to the top, but they just fell off rather than breaking the bridge. We tried hanging weights from the bridge, but again they fell off. So we decided to roll a ball towards the bridge to see if it fell over.

Things to consider

The more force behind as you push, the more force applied to the bridge. So if you roll a ball hard the bridge is more likely to fall over than if you roll gently.

To reduce the variable effect of this, the same person rolled the same ball from the same distance each time, trying to keep the force behind the ball the same.


LEGO Bridge

The first bridge fell over straight away, so we strengthened the base, it still fell over.

LEGO Bridge

We strengthened the bridge further with an extra piece of LEGO in the middle and it stayed upright.

LEGO Bridge

What features do you think make a stable structure?

Don’t forget Twinkl have some great Science printables to help with your LEGO Science.


Related posts

Test a tower for stability using a pendulum

Can you build a structure using marshmallows and spaghetti?

Make a sweetie house and test for the best ‘cement’

Find out why domes are strong

LEGO Bridge

There are 2 comments

  1. LEGO My Science! 10 Engineering LEGO Activities for Kids - Discovery Center of Idaho

    […] When you are ready to test your bridge, get a cup and start adding pennies, slowly at first. See how many you can add before it breaks. Notice if there are any points that look weak or look like they need more support. Use different shapes such as triangles or trapezoids to test how each shape adds support to your bridge. For more ways to test your bridge, go here. […]

Post Your Thoughts