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Science, Evolution, and Creationism, by the National Academies, focuses on teaching evolution in today's classrooms. Check out the other publications in our online store.
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What is Life?

What is life? Does this sound like a strange question to you? Of course we all know what is meant by the word "life", but how would you define it?

Do all living things move? Do they all eat and breathe? Even though we all seem to know what is meant by saying something is "alive", it's not very easy to describe what "life" is. It's almost as hard as describing where life came from.

Even the biologists (people who study life) have a tough time describing what life is! But after many years of studying living things, from the mold on your old tuna sandwich to monkeys in the rainforest, biologists have determined that all living things do share some things in common:

1) Living things need to take in energy
2) Living things get rid of waste
3) Living things grow and develop
4) Living things respond to their environment
5) Living things reproduce and pass their traits onto their offspring
6) Over time, living things evolve (change slowly) in response to their environment

Therefore, in order for something to be considered to "have life" as we know it, it must possess these characteristics.

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Traveling Nitrogen is a fun group game appropriate for the classroom. Players follow nitrogen atoms through living and nonliving parts of the nitrogen cycle. For grades 5-9.

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Traveling Nitrogen Classroom Activity Kit

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA