Introduce songs and books about insect life to the classroom. Sing classic songs like "Itsy Bitsy Spider" or change the lyrics to well-known childhood tunes to reflect a bug theme. Insects and plants are a popular theme for many well-loved children's books like Eric Carle's "The Very Hungry Caterpillar" and Judy Allen's "Are You a Ladybug." Stories, rhymes and songs will get the children acquainted with different varieties of insects and their garden habitats.
Make various garden and insect crafts with the children to teach them about basic plant and insect biology. Make ladybugs, spiders, caterpillars and butterflies out of construction paper so students understand their anatomy. Bring leaves in from outside and let the kids make crayon rubbings over the leaves. Discuss the results with the children, paying attention to the size, vein patterns and symmetry of the leaves.
Bring examples of nature into the classroom. Set up a center where the students can handle garden elements such as flower cuttings, leaves, twigs, grass and soil. Collect ladybugs and other insects and put them in specimen jars for the children to observe. Set up a caterpillar habitat in the classroom so the students can witness the caterpillars building into cocoons and emerging as butterflies firsthand.
Take the children out into a naturalization area in the schoolyard or to a nearby park. The best way to learn about plant and insects is to visit their natural habitat. Ask the students to use their senses to observe the sights, smells, sounds and textures of the plants and to count how many insects they see as they explore the area.