Fun Science with Fruits and Vegetables – Symmetry in Nature

Fruits and vegetables are important and useful. And your kids might possibly find them more appealing after you explore them together. Kids are natural scientists and they are drawn to activities that use their observational skills. So next time you come back from a grocery store look carefully at what you brought home. The bigger the assortment of fruits and vegetables, the more fun you will have. The designs and structures you will discover inside your harvest will surprise and fascinate you!  

 

Supplies needed

Washed fruits and vegetables

Hand-held mirror without a frame

If you don’t have a mirror, use a string

Notebook and pencil, if the kids are old enough to take notes

 

Procedure

Select one item and ask the kids to examine it carefully paying close attention to shape, size, and texture.  

Our cactus fruit is oval, small and slightly prickly. 

 

Ask, “what do you think it’s going to look inside when I cut it?”  

We are new to cactus fruit, so my kids made a prediction that it will be green inside, similar to a kiwi. 

 

Nope!

Now cut it bilaterally, so that both sides are nearly identical. 

 

Ask, “What do you see?” “Is it symmetrical?” “How can we check, if it is?”

 

Give children a flat mirror and ask them to find the line of symmetry.  A line of symmetry divides the object into two mirror-image halves. 

 

“Does the reflected image in the mirror looks like the other half?”  

 

“What kind of symmetry did we find?”

 

My kids were much more willing to give it a taste try after exploring it extensively.  

 

Cauliflower 

Cauliflower presented some challenges.  Is every branch similar to the entire cauliflower?  Is there the same number of flower buds on opposite sides?  

 

Each fraction (or each flower bud in cauliflower) has the same geometrical pattern as a whole vegetable.  Which means cauliflower has what is known as expanding symmetry or evolving symmetry.  You can learn more about fractals here.  My kids were not too interested in fractals at this point.  They were very excited when we could finally split it in half.  And eat it with dip.  

 

The rest of this cauliflower went into a delicious soup…  Yum!

 

Green Pepper

Older kids can draw the inside of the fruit. Make it scientific: label the design and write a few short sentences to describe the findings.  

 

Apple

If you have more than one fruit of the same kind make both horizontal cut and vertical cut.  

What different patterns and designs emerge from different cuts?  

 

Watermelon

Watermelon exploration didn’t go as planned. While we were driving home we decided to cut the watermelon in half, find the line of symmetry and measure the distance from the center to the edge on both sides to see if they are exactly the same length.  

 

 

But as soon as my kids saw this beauty, all they wanted to do is EAT it!  There is always next time.  

 

Green Cabbage

The spiral pattern of green cabbage fascinated us.  Mathematicians came up with complex algorithms to explain this spiral pattern.  Maybe one day your child would be the one explaining it to you.    

 

Cucumber

Cucumber is a fruit because it develops from a flower and contains seeds.  

 

You will get a different pattern from cutting it vertically and horizontally. 

 

I hope we inspired you to take a closer look at the fruits and vegetables in your fridge. What do you buy on a regular basis? Share your photos with us!

 

If you want to learn more about different kinds of symmetry, I created a whole unit study with 26 hands-on Symmetry activities.  You can find the full description here and it’s available for free.