Model NGSS Lessons: Kindergarten - 3rd Grade

Document Type

Teacher Resource

Grade Level

Grade Level: 3rd Grade

Publication Date


Background Information

All living organisms go through life cycles, which consist of stages from birth to death. While these stages are similar, the appearance of organisms in different stages varies. An awareness of child development is important to consider while teaching life cycles. Some research indicates that when a student is in second grade, there is a shift in his or her understanding of organisms, from representations based on perceptual and behavioral features to representations that are more scientific. Children may begin to understand death as the cessation of life processes at about 9 or 10. People of all ages have a much narrower definition of animal that biologists do. Students typically think of animals as terrestrial mammals. Children do not often think of humans as animals. Humans, insects, birds, and fish often are thought of as alternatives other than animals, not as subsets of animals.


Performance Expectations

3-LS1-1- From Molecules to Organisms: Structures and Processes

Develop models to describe that organisms have unique and diverse life cycles but all have in common birth, growth, reproduction, and death.



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