Spring is nature's laboratory
When the days grow longer and the ground begins to warm, something remarkable starts happening beneath the soil. Seeds that have been dormant through winter begin to germinate — splitting open, sending roots downward and shoots upward, transforming from tiny dry specks into living plants.
For children, this is science at its most tangible. You can hold a seed in your hand, plant it, and watch life emerge. Here are five experiments that use seeds and growth to explore real science — no special equipment needed.
1. Bean in a bag
What you need: A zip-lock bag, a paper towel, a bean (runner beans or kidney beans work well), water, tape.
Dampen the paper towel, fold it, and place it inside the zip-lock bag with a bean resting against it. Seal the bag and tape it to a sunny window. Within a few days, the seed will begin to crack open. A root will emerge first, growing downward, followed by a shoot growing upward.
The transparent bag is what makes this experiment special. Children can watch the entire germination process without disturbing the seed. They can see the root hairs, the bending of the shoot toward light, and the gradual unfolding of the first leaves.
STEAM learning: Germination, plant biology, observation, conditions for growth.
2. The sunlight test
What you need: Four identical pots or cups, soil, seeds (cress or radish grow quickly), water, and four locations with different light levels.
Plant the same type of seed in four identical containers with the same soil and the same amount of water. Place one in full sunlight, one in partial shade, one in a room with only artificial light, and one in complete darkness (a closed cupboard).
Water them equally and observe over two weeks. The results are striking. Plants in full sunlight will be shorter and sturdier with green leaves. Plants in darkness will grow tall and pale — stretching desperately toward any light source — a phenomenon called etiolation. Plants in the dark produce elongated stems because the plant is using its energy reserves to grow as tall as possible to reach light, rather than investing in leaves and chlorophyll.
STEAM learning: Photosynthesis, variables and controls, experimental design, plant hormones.
3. Soil comparison
What you need: Three containers, three different soil types (garden soil, sand, and compost or potting mix), the same type of seed, water.
Plant the same seeds in three different soil types, keep everything else the same (light, water, container size), and observe which soil produces the best growth. This experiment introduces a fundamental scientific concept: the fair test. By changing only one variable (soil type) and keeping everything else constant, children learn how real experiments are designed.
Garden soil, sand, and compost behave very differently. Sand drains quickly and holds few nutrients. Compost retains moisture and is rich in organic matter. Garden soil falls somewhere in between. The differences in plant growth will be visible within a week or two.
STEAM learning: Soil science, fair testing, variables and controls, plant nutrition.
4. Measuring growth
What you need: A fast-growing plant (sunflower seedlings are ideal), a ruler, graph paper or a notebook.
Plant a seed and, once it sprouts, measure its height every two days at the same time of day. Record the measurements in a table and plot them on a graph. Over several weeks, the graph tells a story: slow initial growth, then a rapid phase, then a levelling off.
This transforms a simple gardening activity into a mathematics and data science project. Children practise measurement, recording, and graphing — three skills that underpin all of science. And because they are tracking a living thing they planted themselves, the data feels meaningful.
STEAM learning: Measurement, data recording, graphing, growth patterns, prediction.
5. The plant journal
What you need: A notebook, coloured pencils, a plant to observe (any of the above experiments, or a plant in the garden).
A plant journal combines science and art. Every few days, the child draws the plant, notes any changes, records measurements, and writes questions or observations. Over time, the journal becomes a beautiful document of growth — both the plant's and the child's.
The drawing aspect is important. When children draw a plant, they look at it more carefully than when they simply glance at it. They notice details — the way a leaf curls, the colour changes in a stem, the tiny hairs on a bud. Scientific illustration has a long and honourable history, and for good reason: drawing is a form of seeing.
STEAM learning: Scientific illustration, observation, documentation, botany, data over time.
Watch, wait, and wonder
Growing plants teaches something that is increasingly rare in a world of instant results: patience. Seeds do not sprout on demand. Growth cannot be rushed. The child who checks their bean bag every morning and sees no change is learning that nature works on its own schedule — and that waiting is part of the process.
This article is part of the Good Atoms blog — helping families discover the wonder in science, technology, engineering, arts, and mathematics.