An introduction to human somatic cells, along with the different physiological responses that take place. The images and literature are easy to understand; this may be acceptable for children as young as those in elementry. It does not go into great detail which is suitable for the audiance.
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Michael Coelho (Student)
Material like this could have a conerstone position in teaching biology at these grade levels. The only issue with it would be the link to a wikipedia article as it isn't always the most credible source and employers might not approve the use of this in the classroom.
Kurt Shults (Student)
This website has a good amount of simple, relevent pictures that should be easy to understand. It is also nice that there is a recommended grade level for material.
Joseph Rodrigues (Student)
Another great find! This website is great for teachers as it provides information and interactive quizes that students can complete.