Appendix 4: Tessa learns about physics

Today at Playgroup, Tessa put a baby in the dolls buggy and pushed the buggy outside onto the deck. Then she carefully turned the buggy round and tried to push it back inside. She pushed as hard as she could, but the buggy just wouldn’t roll over the small step leading back into the playroom.

Undaunted by this set back Tessa stepped back then stepped forward pushing hard. When this didn’t work, she lifted the handle of the buggy which lifted the back wheels off the ground. With the back wheels in the air, she tried again to push the front wheels over the entrance. When this failed, she seemed rather perplexed as she looked closely at the wheels and thought about the problem.

Then with an air of determination she lifted the handle as high as she could leaning way back and when all 4 wheels were off the ground, she carried the whole buggy inside. Puffing from the exertion Tessa dropped the buggy as soon as she was inside. Then she quickly pushed it around in a circle and straight back outside onto the deck where she circled round for another run at the entrance.

Once again, she experimented with a straight push with all 4 wheels on the ground and with a half lift with the back wheels raised. When these techniques failed again, she tried bending her knees and making herself lower then pushed from this squatting position. Then in frustration she performed the full lift leaning way back and carrying the buggy through the door again.

Tessa continued to push the buggy outside and back in over and over and over again. She invested a huge amount of effort and energy in the straight push, the half lift and the squatting push over and over again. Eventually she rocked the buggy in frustration and as she pushed down on the handle the front wheels lifted and it slid inside. Success at last!

As quickly as she could Tessa circled back outside and rocked the buggy till the front wheels lifted and once again it slid inside. One of the adults said, “Wow that really works Tessa when you push down on the handle the front wheels lift up". After discovering the tricky mathematical concept of leverage and perfecting this new skill Tessa left the buggy after a grand total of 16 trips in and out of the playroom.