Optional Activities
Living vs. Nonliving Collage
Reinforces the classification of living and nonliving items by having learners create a divided visual collage. By analyzing and sorting various images, participants practice identifying key biological characteristics (such as growth, energy use, and response to the environment) while reflecting on the nuanced boundary between objects that were once alive and those that are inanimate.

Life Scavenger Hunt: 
Walk through your home and yard and find 10 things. Sort them into three categories: living now, once living, never alive. The tricky ones (wood, bread, hair, dead insects, paper) generate the best discussion. Revisit the characteristics of life to settle arguments.

Make a Characteristics of Life Poster: 
Create a visual reference card showing all seven characteristics of life with a simple illustration for each. Keep it up during the biology units that follow, learners can reference it throughout Lessons 10–20 as new organisms come up.


Digging Deeper Activities

Are Viruses Alive?: 
Research both sides of the virus debate, viruses have genetic material and evolve, but they can’t reproduce without a host cell and have no metabolism of their own. Write a one-paragraph argument for each side, then state your own conclusion and explain why.

Astrobiology Thought Experiment: 
NASA uses the definition “life is a self-sustaining chemical system capable of Darwinian evolution.” Is this a better or worse definition than the seven-characteristics list? Could there be life on other planets that doesn’t match either definition? Design a hypothetical alien life form and test it against both definitions.

Moral & Ethical Discussion: What Counts as Life?
Engage learners in critical thinking about the nature of life and the responsibilities that come with it. Through age-appropriate discussion prompts and practical sorting exercises, learners progress from recognizing basic needs of living things to evaluating complex ethical dilemmas regarding how we treat different organisms based on their perceived value.

Onion Skin Cell Observation
Allows learners to witness the fundamental building blocks of life firsthand. By preparing a thin, transparent layer of onion skin on a microscope slide, learners can observe the distinct cell walls and nuclei that prove the onion is a living organism, helping them bridge the gap between abstract definitions of "cells" and observable biological reality.

Example Lab
Virtual Microscope