Seed Sprout Science!
In this activity, we are going to explore the science of plants! This simple experiment brings authentic science into the classroom as we compare the effect of water on plant growth. These flowers are a perfect introduction to Spring and are an easy Mother’s Day gift!
Let’s Begin!
Learning Objectives/Opportunities
Build basic knowledge about plants
Science process skills: observing, measuring, experimentation, recording and sharing findings, using science tools
Developmental Skills: fine and gross motor skills
Next Generation Science Standard
2-LS2-1. Plan and conduct an investigation to determine if plants need sunlight and water to grow.
PA State Standard:
3.1.1.B1. Grow plants from seed and describe how they grow and change.
Let’s Begin!
Materials:
Soil (we recommend Miracle-Gro All Purpose Potting Mix)
Water (distilled water & tap water)
Banana peels
Ruler
Sharpie
Popsicle sticks
Post-it Notes or paper and tape
Seeds (we recommend Marigolds – the seeds are large enough to make observations and they root and sprout quickly)
Instructions:
Set-Up:
Using your ruler, measure four inches from the bottom of your popsicle stick. Place a long black line. This will be the line to which you fill your potting soil.
Find a half-inch below that line. Mark it with a long green line. This is how deep you will plant your seed.
From the green line, mark every quarter, half, and full inch until the bottom of the stick.
From the black line, mark every quarter, half, and full inch until the top of the stick. Leave yourself a little space to write at the top.
Write “Distill,” at the top of one popsicle stick. Repeat with “Tap” and “K” on the other two. Note, K is the chemical symbol for potassium. This will be the potassium water cup.
Let the popsicle sticks dry.
Once dry, place one popsicle stick in each plastic cup.
Next, prepare water
Fill 2 pitchers with water
Toss banana peels into one pitcher
Let the water sit for the weekend
Gentle Disclaimer: Adult supervision and guidance is recommended for STEMSpark activities. We may use materials or ingredients in our experiments that can stain surfaces or clothing, be messy, or slippery. Please be careful and make sure no experiments are put in the mouth and kept away from children under 3.
Hands-on for Little Scientists!
Now that the materials have been prepared, have students fill the cup to the black line with potting soil.
Help students to plant their seed. Be sure to place the seed against the side of the cup and next to the popsicle stick so students can observe and measure root growth. Try using a science tool like a toothpick or tweezers to help with planting.
Have students scoop out 1/4 cup of water from the tap water pitcher and pour into the cup labeled “Tap”
Repeat with potassium water and distilled water.
Observe plant growth daily. Complete seed sprout observation sheets to document daily change as the seed grows roots and blooms. An easy way to include math in this experiment is to include measurement. You can measure:
root depth (how deep the root extend)
the number of root branches
sprout height (how far sprouts extend above soil)
number of sprout leaves
Depending on how small your seeds and roots are, you may need to break out the magnifying glasses!
Science Background
Did you know, many fertilizers include potassium because it helps to stimulate root growth? In this experiment, we observed the effects of water on plant growth.
Tap water frequently includes additives such as chlorine or fluoride, and sometimes impurities like pesticides and arsenic. The different chemicals in tap water may help or hurt plant growth. To test this, we include distilled water as our comparison group.
Distilled water has been boiled, making it a type of purified water.
We additionally include potassium water to see if we can make simple, clean fertilizers for our flowers and gardens.
This activity requires a critical component of experimentation: control of variables. The only thing we want to change between the three cups is the type of water they receive. This means that we need to ensure all other variables are the same. Be sure that:
the pitchers of water are stored at room temperature
the three cups receive the same amount of sunlight
we use the same soil, seeds, and cups for all three plants
If everything else is the same, then we know any differences we observe are due to the type of water it has been receiving. Experiments like this allow scientists to draw conclusions about cause and effect!
Research Connection
Dr. David Sobel at Brown University has been studying scientific skills in children for over a decade. His lab, The Causality and Mind Lab, studies how children develop the ability to reason about cause and effect. Recent research from his lab suggests that young children struggle with controlling variables in a Lego task, however, with direct instruction and practice, children demonstrated increased scientific reasoning skills. For early childhood educators, introducing children to simple experiments like the one here can help them begin to think like a scientist!