Last week as we were checking out Simple Machines, one of the books in Starting With Science kids series, our librarian looked kindly at my kids and noted, “Your son will enjoy this book.” My daughter was standing right there too! Do you get irritated by this kind of sexist comments? Do you say anything? Why shouldn’t my daughter enjoy building simple machines? After all, a circular saw was invented by a woman and so was the first modern programming language (check out those other things invented by women). We happened to like our librarian very much (we even bake her cookies and buns) and she is very patient with our endless questions, so I kept my mouth shut. But I’m happy to tell you that my daughter does indeed enjoy this book as much as my son. One of the things they really liked exploring is inclined plane. If you have cars lover in your family, give it a try. It can be done with things readily available in a home. And you can finally make use of all those loose pennies.
You will need
a long board (a closet shelf worked for us)
2 small yogurt containers or plastic cups
a piece of string
two toy cars of different sizes
lots of pennies
hole puncher to make holes in containers
scissors to cut string
paper and pen to record observations
What to do
1. Poke two small holes near the top of yogurt container on opposite sides. Thread one end of the string through the holes and tie it. Tie the other end of the string to the toy car. Repeat with the second car.
Note: We actually drilled holes in our cars because in my mind I saw lots of experiments that could be done with them this way.
2. Build a ramp. Put a small pile of books on one end of the table. Rest one edge of the board on top. We used a second pile of books to prevent the board from sliding back.
3. Set the cars near the bottom of the ramp. Hang the yogurt containers just over the edge of the board.
4. Drop pennies, one at a time, into the containers counting out loud. And record your observations. Note: In place of pennies you can also try stones, marbles or blocks.
Some questions to get the discussion started:
When does the car start to move?
How many more pennies it takes to move it to the top of the ramp?
Does it take the same number of pennies to move both cars?
What do you think is happening here?
6. Add one more book at a time to make the incline steeper. The steeper the incline, the more pennies you will need. It took us 41 pennies to move truck up the ramp made with 6 books. Questions to ask:
We just added another book how many pennies does it take to move the car now?
More pennies or fewer than before?
How changing the number of books changes the incline?
This is what we used to record our observations.
The steps outlined above is what we did to get the exploration started. After that I left kids to their own devices and they came up with many inventive ways to play with the ramp: varying vehicles, books, inclines, objects to move up and down the ramp. When I wanted to put it away at the end of the day, they implored me to leave it as there were other things they wanted to try with it the next day.
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