Plant a seed, give it what it needs, and watch the days go by. Find out what happens in the dark, follow colored water up a stem, and switch on a leaf's food factory.
The big ideas
What the levels teach, in grown-up words.
Plants need light, water, air and soil. Take light away and a seedling grows pale, thin and floppy as it stretches to find some. Take water away and it wilts. Too much water drowns the roots, which need air too.
Each part has a job. Roots take in water and hold the plant steady, the stem carries water up through tiny tubes, leaves make food from sunlight, and flowers make seeds.
Leaves make food from light. In photosynthesis, leaves use sunlight, water and carbon dioxide from the air to make sugar, and they give off the oxygen we breathe.
A fair test changes one thing at a time. Two pots that differ only in light show what light does. If two things changed at once, you couldn't tell which one mattered.
Seeds travel, and flowers need pollinators. Wind, animals and water carry seeds to new places. Bees move pollen between flowers, which is what lets a flower make fruit and seeds.
Try it at home
Quick experiments that match the game.
Bean in a bag. Put a dried bean in a clear bag with a damp paper towel and tape it to a window. Check it every day and watch the root and shoot appear.
The dark cupboard test. Grow two identical seedlings, one on a windowsill and one in a cupboard. After a week, compare their color and height.
Celery stripes. Stand a celery stalk in water with a few drops of food coloring. The next day, snap it and look for the colored tubes.
Seed hunt. On a walk, look for seeds that fly, stick or float: dandelion clocks, burrs on socks, winged maple seeds.
Ask after playing:
What happened to the plant that lived in the dark?
Why should we only change one thing in a fair test?
What does a leaf make from sunlight, water and air?