Kids are going to love this fun, hands on science experiment exploring why do leaves change colors. No fancy equipment required; easy to do in a classroom, after school, or homeschool setting. Great for kids from preschool and kindergarten to 1st-6th grade too.

why-do-fall-leaves-change-colors-fall-science-experiments-for-kids

I love fall and all the leaves changing color; It is by far one of my favorite times of the year. There is something refreshing about fall from the crisp air to the magical colors that fill the horizons.

This week as the leaves in our front yard began to change color the kids became filled with questions.

Was it fairies?
What about the Sun?
Oh I know, it was our gnome with the paintbrush…

This science experiment to discover Why Leaves Change Color was the perfect solution for their curious minds.

Why do Leaves Change Color Science Experiment

To delve into why leaves change color kids need to first understand the purpose of leaves.

While on your nature hunt to collect the leaves for this science project is the perfect opportunity to discuss what jobs leaves are responsible for. [FREE leaf nature hunt to teach kids about types of trees]

Plants are responsible for creating the oxygen that we breathe. They do this by absorbing water from the ground and carbon dioxide from the air. Using sunlight (through photosynthesis) they turn water and carbon dioxide into oxygen and glucose. Oxygen is what we need to breathe and glucose is what the plant uses to grow. The term photosynthesis means “putting together with light”. The chemical that plants use to make photosynthesis is chlorophyll. Chlorophyll is the same chemical that gives plants their green color.

Supplies Needed:

- Glass Jars
- Coffee Filters
- Leaves
- Rubbing Alcohol
- Notebook and Pencil to Record Observations

Chromatography Science Experiment

To find the answer to this question kids will need to collect a couple handfuls of leaves.

Once collected, leaves need to be sorted by color into containers. The sorted cover leaves should then be covered rubbing alcohol and grind leaves up.

Once full mashed up the rubbing alcohol should show the colors of the leaves.

Making a cone shape with the coffee filters place the tip into the mixture and allow it to sit long enough to absorb the liquid.

You will immediately be able to see the coffee filters absorb the liquid.

HINT: How long it takes to completely absorb the color will depend on how many leaves and how much rubbing alcohol was used.

After 12 hours ours hadn’t fully absorbed the liquid but you could begin to see the effect.

Beautiful isn’t it?

As the liquid travels up the coffee filter it separates all the colors that were inside the leaf.

The Science Behind Why Leaves Change Colors

During winter, the days get shorted affecting the amount of sun the leaves are exposed to. Due to this lack of sunlight, plants go into a resting state and live off of the glucose that they stored over the summer. As they shut down for the winter, the green chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange colors. Small amounts of these colors have been in the leaves all along. For example in Maple trees the bright red that shows up is a result of excess glucose being trapped in the leaves.

This is an experiment that is pretty fascinating no matter your child’s age.