For this project, described on the Educator's Reference Desk website, you need a variety of seeds to show the children, pictures of the grown plants and their fruits or vegetables (or bring in the actual fruit or vegetable), one or more lima beans per child and one small, disposable cup per child. Label each disposable cup with a child's name, and set them aside.
Show the children a seed. Ask if they can guess what kind of seed it is. Show them the matching picture, or the actual fruit or vegetable, the seed will grow into. Repeat this process with the other seeds. Give each child a lima bean seed. Allow them to study the seeds and explain what the seed will grow into. Tell the children the seeds have a coat to protect them until they have all the things they need to start growing. Talk to the children about what plants need to grow. Fill each child's disposable cup with enough water to cover the seeds. Allow the seeds to soak overnight. The next day, tell the children to carefully take their seeds out of the cup. Ask them if they notice any changes. Help each child open one of her seeds in half to see the baby plant inside.
This project will allow the children to see roots growing under the soil. You need lima bean seeds, one clear plastic cup for each seed, enough garden soil to fill each plastic cup about 3/4 full, and masking tape. Label each cup with a child's name using a small piece of masking tape.
Help the children put the soil into the cup, plant the lima bean seed and water the seed. Keep the seeds in a warm place, away from drafts. Observe the seed each day, add water if needed and talk about changes the children notice. Their plants will poke above the soil and begin to grow leaves. Eventually, roots will be visible through the clear plastic cup.
To help the children learn why plants need roots, you need a plastic drinking straw per child, a disposable cup 1/2 full of water, milk or juice per child, one white carnation per child plus one for yourself and food dye.
Prepare a carnation ahead of time by giving the stem a fresh cut. Fill a disposable cup with water and add a few drops of food dye. The stem will carry the dye, along with the water, up into the flower, adding a pretty color to show the children how the roots work.
Tell the children that a plant's roots bring water and nutrients from the soil up to the plant. Pass out the cups of water, milk or juice and give each child a straw. Tell them the plant's roots act like a straw and let them drink through their straws. Show them the carnation you prepared ahead of time and explain that the stem carried the colored water into the flower, like roots would do. Help the children prepare the cups for their carnations. Allow them to take their flowers home when they are finished with them in class.
Take the children to see a backyard garden or farm, if there is one close enough. Explain the journey the fruits and vegetables take to the grocery store. They might also enjoy picking their own fruit or vegetables at a pick-your-own farm or orchard.