We are celebrating National STEM Day with an activity from our Green Teens! In posting weekly STEM-related activities, our goal is to help develop your STEM Explorers’ interests in science, technology, engineering, and math. Partaking in STEM activities enhances critical thinking and communication skills, while encouraging collaboration and teamwork.
This week, we are doing an experiment using leaves. During the fall, the green leaves on trees turn shades of red, orange, and yellow. Different colored pigments are hidden during the warmer months and only appear when the green chlorophyll pigment, which helps the tree make its own food, starts to break down as the weather gets colder. You and your STEM Explorers can figure out what pigments are found in leaves using just a few simple materials: leaves from the same tree, rubbing alcohol, a jar, plastic wrap, coffee filter, hot water, and a bowl. 🍁
1. Break up your leaves into tiny pieces and place them inside your jar.
2. Pour enough rubbing alcohol into the jar to cover the leaves.
3. Stir and mash the leaves until the liquid inside the jar looks green and your leaves are mushy.
4. Place plastic wrap over your jar, place it in a small bowl, and pour hot water into the bowl.
5. Leave it to sit for 30 minutes, occasionally swirling the jar to mix the contents. If after 30 minutes, the liquid is not dark green, wait a little longer.
6. Cut a strip from your coffee filter that is long enough to hang over the side of your jar while the bottom reaches to the liquid, taping it at the top if needed.
7. The liquid will travel up the coffee filter and as it moves, the different colored pigments will be separated from each other, creating beautiful bands!
8. Try this with another kind of leaf. Does it look the same or different?
Special thanks to our partner National Grid for their support of the STEM Explorers powered by Green Teens program.