Why Do Leaves Change Color? Autumn Science

My kids ask every year why the leaves change color, and I finally found an experiment to show them the colors of leaves, the colors they change, instead of just trying to explain it. This is fun and easy to do. I love getting hands-on with science with my kids, they learn a lot more when they are involved.

Why Do Leaves Change Color_ Autumn Science

Why Do Leaves Change Color?

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It’s really simple actually, just a few things from around your house and yard.

What you need:

Why Do Leaves Change Color? Autumn Science

I started this by asking my kids the question that they ask me “why do leaves change color?” The answer I got, was that they change because it is autumn, a simple answer and it completely makes sense for kids. They change because the season changes.

I grabbed 3 different leaves – 2 red leaves from the vine crawling up our shed, 2 green leaves from the vine crawling up our shed, and 2 green leave from a tree.

3 jars, one for each set of leaves I had.

Tear the leaves up and put them into each jar.

Why Do Leaves Change Color? Autumn Science

Pour just enough rubbing alcohol into each jar to cover the leaves.

There are two (or many more) ways to do the next part. You can cut your coffee filters into strips, or roll it into a cone shape, either will work.

Why Do Leaves Change Color? Autumn Science

Now you wait. It took 6-8 hours before we saw anything, and 24 hours before it was clear. I took these pictures after about 24 hours.

The Why Behind It?

Chlorophyll would be the answer. It is the dominant pigment in the leaves (green). It covers the other colors that are there in the leaves, the reds, and yellows. The leaves stay green the water that the tree takes in through its roots.

Why does the green disappear? The trees realize that summer is coming to an end (due to less sunlight) and stop taking in so much water. Without the water, the green chlorophyll starts to disappear and the other colors in the leaf and the yellow and the orange can be seen.

So leaves don’t really “change” color so much as lose color. You can clearly see the different colors on the filter. Do this with your kids. You only need some coffee filters and rubbing alcohol. You have kids, so you probably already have the rubbing alcohol and coffee filters.

Similar posts that you may be interested in:

Disappearing Color Science Experiment

Charlotte’s Web – Watercolor Web