Reading the book "Jack and the Beanstalk" can be the basis of an activity centered around edible plants. One activity involves sprouting beans into plants and watching the plants grow in the classroom. A more immediate activity is to hand out bean pods to all students and have them open up the pods to find the beans inside. Kids can taste the beans to see what raw beans taste like. One twist to this activity is to also hand out pea pods, as preschoolers may be more willing to taste the fresh peas.
The book "The Little Red Hen" is a preschool staple that teaches kids about teamwork and the fruits of labor when one works hard. The grain of wheat is the basis of the book and can be used as an edible activity for younger children. Let kids taste, touch and hold fresh-cut wheat. You can supplement this activity by having an assortment of wheat-based food items available for kids to taste, such as whole wheat bread, cereal made with whole grains and wheat germ.
If you have a group of curious preschoolers, you can base an edible plant activity around both taste and smell. Use shoeboxes with slits cut out of the lids. Inside each box, place edible items that have a distinguishable smell. The first phase of the activity is to have kids smell the item through the opening and guess what is inside. The second step involves having kids taste edible plants while blindfolded to see if they can properly guess which item they sampled. Plant choices for this include dill, oregano, mint, garlic and onions.
Preschoolers are at an age where most things learned are new and foreign to them. One way to get children interested in a lesson on edible plants is to offer up an assortment of odd, unique and intriguing plants that are edible. Though not all kids will take a bite of everything, using an array of items helps illustrate how many various foods are derived from the plant world. Good options to use for this activity include starfruit, dragonfruit, chrysanthemum, dandelion, honeysuckle, lavender and okra.