Discuss with preschoolers the characteristics of living and nonliving objects. Bring items in both categories to class; show them to the children one by one and ask them if they are living or nonliving. Ask them why they think they belong to each category. Explain to the preschoolers the characteristics of living things, such as that they eat, grow and reproduce. Point out that nonliving things don't do any of those actions. Continue to use examples, and answer questions the children might have about this topic.
Give your children two bags, one for nonliving things and one for living. Write on each bag "Living" and "Nonliving." Hand out bags of different colors or make especial bags ahead of time. Take your preschoolers outside or for a walk. Ask them to collect things for each bag. Collect rocks, dry leaves, green leaves or insects. Bring the bags to class and discuss what they collected.
Use a cut-out activity to help children visualize living and nonliving things. Divide the children into groups. Give each group a piece of construction paper previously divided in two sides, with "Living" written on one side and "Nonliving" written on the other side. Give the groups magazines and books they can cut out. Instruct each team to look for living and nonliving objects to cut and paste onto the piece of paper. Let each group discuss what to cut and paste in each category.
A show-and-tell activity allows children to share with their families what they are learning in school. Instruct your kids to go home and discuss this topic with their parents. Send a note to parents asking them to reinforce this lesson at home. Ask your students to bring one living and one nonliving item to class. Give them rules of things they cannot bring, such as big pets. In class, allow the children to explain each item they brought and why they are living or nonliving.