This Immersion Unit provides a coherent series of lessons designed to guide students in developing deep conceptual understanding that is aligned with the standards, key science concepts, and essential features of classroom inquiry (as defined by the National Science Education Standards). 

Unit Overarching Concepts

• Populations of living organisms change or stay the same over time as a result of the interactions between the genetic variations that are expressed by the individuals in the populations and the environment in which the population lives.
• Science knowledge advances through inquiry.

Unit Supporting Concepts

• Individual organisms with certain variations of traits (adaptations) are more likely than others to survive and reproduce successfully.When environmental conditions change it can affect the survival of both individual organisms and entire species.
• Natural selection determines the differential survival of groups of organisms.
• A small advantage in escaping a predator, resisting a drug, etc. can lead to the spread of a trait in a modest number of generations.
• Mutations are a source of variation in an individual’s genotype, and it can result in a change in phenotype––good or bad.
• Scientific progress is made by asking meaningful questions and conducting careful investigations, using appropriate tools and technology to perform tests, collect data, analyze relationships, and display data.
• No matter how well one scientific explanation fits observations, a new explanation might fit them just as well or better, or might fit a wider range of observations. In science, the testing, revising, and occasional discarding of explanations, new and old, never ends.

This unit was developed through the large Math and Science Partnership project called System-wide Change for All Learners and Educators (SCALE), involving a collaboration among Los Angeles School District educators, California State University science and education faculty, and UW-Madison SCALE staff.