3D shape inquiry continues... - Roll or Tumble?

"Hey Mom! Look! The grapes are rolling, just like ball!", exclaimed Nidhi tilting her snack tray.
"Why do you think it rolls?", I queried and she instantly replied back "Because they are spheres."
"Balls are spheres too and they bounce", Sid joined the conversation. Interesting connection.
"So, do all things that roll, also bounce?" I wondered aloud.
"No", Sid answered confidently. To support his hypothesis, he pulled out one of Nidhi's cylinder made of card-stock, dropped it on the floor and reported "See, it does not bounce but it rolls."

This conversation inspired Nidhi to carry out her own little experiment to find out objects that rolled and objects that tumbled.

Here is what she did and observed.

Rolling a cylinder block on flat surface

Cylinder and flat surface

Trying to roll a cuboid on flat surface and observing that it just tumbles.

Does a cuboid roll?

Trying to roll a cuboid on an inclined surface and observing that it still only tumbles or slides.

Will it roll if on inclined surface?

Sorting the objects on a piece of paper based on her observations.

Recording her observation

Here is a final recording of her observation.

Final record

As you can see she had way more fun with objects that roll. :)

Education is a natural process carried out by the child and is not acquired by listening to the words but by experiences in the environment

-Maria Montessori