We want children to eat healthier and one way to reach this goal is to involve children in growing plants they can eat. Watching plants grow from seeds to edible crops during one or two elementary school grading periods is entertaining and educational. There are simple, low-cost gardening activities that third graders can do by themselves or in small teams that require only a little supervision, preplanning and a few supplies.
If you have a bit of land on school grounds that can be used for a gardening project, your third grade students can plant a few easy-to-grow, edible crops such as lettuce, radishes, carrots, and spinach that are ready to harvest in six to eight weeks. Prior to planting, the ground needs to be prepared which means removing existing plant material, turning the soil, and breaking up any clots of dirt. It is best to work organic matter, composted materials, and fertilizer into the soil at least two weeks before planting.
Preparing the garden bed requires some adult help that may be provided by a parent group. Your third grade students can help with clearing weeds and smoothing the soil. Classroom instruction on plant activities may include discussing planting time restrictions and the effect of water, temperature, sunlight, and nutrients on plant health.
Have your students plant seeds in the garden and help with watering and clearing weeds as the plants grow. Check and record the plant's growth each week. Select seeds that are easy, rapid growers because third graders do not have a lot of time or patience. For example, Black-Seeded Simpson lettuce will sprout in a few days and be ready to harvest in about six weeks.
Plan a special day for the third grade students to help harvest the plants and enjoy eating and sharing the food they helped grow.
Window Herb Garden
A good indoor plant activity for third graders is growing herbs in containers placed in a window. Because herb seeds are often difficult to germinate, use seedlings or transplants. Select containers that are several inches deep in order to hold the plant root ball. Good herbs for container growing include thyme, sage, parsley, chives, mint, and basil.
Herbs are aromatic and third graders will enjoy doing blind identification tests based on the smell of the leaves. You can also encourage students to find recipes using the herbs being grown and to find samples of herbs in the grocery store and in their kitchen at home. A window herb garden needs little care beyond occasion watering and sunlight. Even if your window light does not provide the six hours a day of sun needed, the overhead fluorescent lights in most third grade classrooms will provide sufficient supplemental light.
Your third graders can create a simple hydroponic garden using an old aquarium. Plant activities in creating a hydroponic garden include painting the inside of the aquarium black, cutting a piece of Styrofoam to fit into the aquarium and making several holes in the Styrofoam to support plant containers. The Styrofoam sits on top of a layer of liquid, nutrient solution that feeds the plant roots. Hydroponic growing introduces students to soilless plant growing and the plants in that rich environment grow more quickly than in outdoor gardens. Herbs and salad fixings grow well in hydroponic growing systems.