If you have only four weights, where could you place them in order to balance this equaliser?
Can you work out what is wrong with the cogs on a UK 2 pound coin?
What happens when you turn these cogs? Investigate the differences between turning two cogs of different sizes and two cogs which are the same.
Meg and Mo need to hang their marbles so that they balance. Use the interactivity to experiment and find out what they need to do.
Meg and Mo still need to hang their marbles so that they balance, but this time the constraints are different. Use the interactivity to experiment and find out what they need to do.
Mo has left, but Meg is still experimenting. Use the interactivity to help you find out how she can alter her pouch of marbles and still keep the two pouches balanced.
George has explained his thinking nicely by looking at all the different combinations.
Go to last month's problems to see more solutions.
This article for teachers sets out some ideas for introducing children to some of the concepts at the root of mechanics.
The second of two articles explaining how to include talk in maths presentations.