Did you see rubbish on your way to school today?


Wouldn’t it be great to organise a day of tidying up? It’s a big job, so you’re going to need some rubbish grabbers.

How can you find the best grabber for the job?

Build two grabbers.


You’ll start by testing these 2 grabbers. You’ll also need a controller.

If you have enough time, you should build and test your own design.

Gather the ‘rubbish’.


You’ll need :

  • 1 LEGO brick
  • 1 empty plastic bottle
  • 1 ball of crumpled paper  
  • 1 stack of LEGO wheels
  • 1 apple (or any round fruit)

You can replace the apple with any object of the same size and weight.

Play this program to test the 2 grabbers.

SPIKE Invention-Squad Super-Cleanup Step04-Program - en-gb

Which one do you think works the best?

Test #1: Object Size


Try to use each grabber to pick up the empty bottle, crumpled paper and LEGO brick.

Give it a score:

  • 1 point if it grabs, lifts and moves the object
  • 0 points if it grabs but drops the object
  • -1 point if it doesn’t grab or lift the object

Note your scores in a table.

Test #2: Object Weight


Repeat the last test using the LEGO wheels, crumpled paper and an apple. 

Note your scores in another table.

What’s your conclusion?

  • Which grabber is the best for picking up small objects?
  • Which grabber is the best for picking up heavy objects?

Collect more objects from around your classroom and predict which grabber will be the best at grabbing and lifting them.

How did you do?


Record a video explaining what you’ve been working on.

Make sure to include your whole team, even the camera-shy people!