Does the human body evolve as quickly as human culture? With a stellar 15-minute video, explore the trait of lactose intolerance. Only about 1/3 of human adults seem to still have the enzyme lactase and therefore, the ability to digest...

Young scholars learn that heredity comes down to the flip of a coin with this cross-curricular math and science lesson. Using smiley faces as a model, students toss coins to determine which dominant or recessive traits...