Simple machines and a civil engineer


We have been thinking about simple machines lately.

The children lifted this stack of books and then used the inclined plane to pull them up.

Which one was easier?

The inclined plane of course!


Tommy’s dad Eric, who is a civil engineer, came in to talk about simple machines and how we use them when building roads or parking garages.

He said the first thing to do is start with a plan.

Eric told us about asphalt that is made of tar, sand and gravel.


Tommy helped show pictures from a book to help us understand this process.

First, dump trucks put asphalt on the roads.  A dump truck is an inclined plane.


The roller truck then flattens out the asphalt and makes it flat.

The drum rolls out the asphalt.  This is also a simple machine.


Next we had an activity.  The children were able to make their own roads with a simple machine.


We made our own “asphalt” with sand and some water.


Water was added but this “road” looked way too bumpy to drive on!


Eric told us how a roller works and we could see it in action.



We could see that after using a roller, the “road” was flat and ready to use.


Eric also used a block to stomp down the sand.  This was not as effective because it used up more energy and the road was not as level as when flattened by the roller!

We learned simple machines are easier to use and require less energy.

The children then took turns rolling over the sand to make smooth roads.

Big thank you to Eric and Tommy for teaching us about simple machines!