To set this up I gave the girls some rope and instructed little Bear to try and pull Bug (big sister) so that Bug would have to take a step. I instructed Bug to pull back and resist her little sister but not try and pull her over.
Here little Bear was pulling and big sister just held on with one hand. It was pretty easy to resist the little one! So then we anchored the rope to a pillar and looped one end over a piece of PVC pipe (a broom would work as well) and repeated our instructions with Bug holding onto the PVC pipe or pulley.
Little Bear gave it her best - pulling and tugging but Bug did not move. It did take a few tries to make sure that little Bear pulled straight and not off to the side. Then we increased the number of pulleys or loops. I looped the rope around the pillar and back around the PVC pipe again and repeated our instructions.
Boy did little Bear give Bug a struggle. Bug had to pull really hard against her little sister not to move. It felt like little Bear was quite stronger!
We then switched around and I held the PVC pipe and Bug pulled on the rope. At first she could not move me but I had to try hard to keep the PVC pipe in the same place when we had the multiple loops.
This was a great way for Bug to really feel how increasing the number of pulleys will change the force.
- rope or string
- PVC pipe or broom handle
- Have 2 people hold onto the ends of a piece of rope and pull like in a game of tug-of-war.
- Anchor one end of the rope to something sturdy like a pillar.
- Loop the other end over a piece of PVC pipe that one person holds.
- Have someone pull on the free end of the rope and repeat the tug of war.
- Then loop the rope around the pillar and the PVC pipe again and repeat.
- You can repeat this last step multiple times if you need to.