• 9-12: 1A/H3bc. In science, the testing, revising, and occasional discarding of theories, new and old, never ends. This ongoing process leads to a better understanding of how things work in the world but not to absolute truth.

• 9-12: 1B/H8. Scientists' nationality, sex, ethnic origin, age, political convictions, and so on may incline them to look for or emphasize one or another kind of evidence or interpretation.

• 6-8: 1C/M7. Accurate record-keeping, openness, and replication are essential for maintaining an investigator's credibility with other scientists and society.
• 6-8: 1C/M8. Scientists' personal interests and viewpoints can influence the questions they investigate.
• 9-12: 1C/H6ab. Scientists can bring information, insights, and analytical skills to bear on matters of public concern. Acting in their areas of expertise, scientists can help people understand the likely causes of events and estimate their possible effects.

• 6-8: 3C/M9. In all technologies, there are always trade-offs to be made.
• 9-12: 3C/H5. Human inventiveness has brought new risks as well as improvements to human existence.
• 9-12: 3C/H6. The human ability to influence the course of history comes from its capacity for generating knowledge and developing new technologies—and for communicating ideas to others.

• 6-8: 4D/M5. Chemical elements are those substances that do not break down during normal laboratory reactions involving such treatments as heating, exposure to electric current, or reaction with acids. All substances from living and nonliving things can be broken down to a set of about 100 elements, but since most elements tend to combine with others, few elements are found in their pure form.
• 9-12: 4D/H3. Although neutrons have little effect on how an atom interacts with other atoms, the number of neutrons does affect the mass and stability of the nucleus. Isotopes of the same element have the same number of protons (and therefore of electrons) but differ in the number of neutrons.
• 9-12: 4D/H4. The nucleus of radioactive isotopes is unstable and spontaneously decays, emitting particles and/or wavelike radiation. It cannot be predicted exactly when, if ever, an unstable nucleus will decay, but a large group of identical nuclei decay at a predictable rate. This predictability of decay rate allows radioactivity to be used for estimating the age of materials that contain radioactive substances.

• 9-12: 4E/H6. Energy is released whenever the nuclei of very heavy atoms, such as uranium or plutonium, split into middleweight ones, or when very light nuclei, such as those of hydrogen and helium, combine into heavier ones. For a given quantity of a substance, the energy released in a nuclear reaction is very much greater than the energy given off in a chemical reaction.

• 9-12: 8C/H3. Nuclear reactions release energy without the combustion products of burning fuels, but the radioactivity of fuels and their by-products poses other risks.

• 9-12: 10G/H1b. In their laboratory in France, Marie Curie and her husband, Pierre Curie, isolated two new elements that caused most of the radioactivity of the uranium mineral. They named one radium because it gave off powerful, invisible rays, and the other polonium in honor of Madame Curie's country of birth, Poland.
• 9-12: 10G/H4b. Nuclear weapons and energy remain matters of public concern and controversy.
• 9-12: 10G/H5. Radioactivity has many uses other than generating energy, including in medicine, industry, and scientific research in many different fields.

• 9-12: 12A/H5. Curiosity motivates scientists to ask questions about the world around them and seek answers to those questions. Being open to new ideas motivates scientists to consider ideas that they had not previously considered. Skepticism motivates scientists to question and test their own ideas and those that others propose.

• RST.11-12.6 Analyze the author's purpose in providing an explanation, describing a procedure, or discussing an experiment in a text, identifying important issues that remain unresolved.

• RST.11-12.9 Synthesize information from a range of sources (e.g., texts, experiments, simulations) into a coherent understanding of a process, phenomenon, or concept, resolving conflicting information when possible.

• RST.11-12.10 By the end of grade 12, read and comprehend science/technical texts in the grades 11—CCR text complexity band independently and proficiently.

We highly recommend this resource to help students grasp the hardships and obstacles often faced by pioneering scientists, especially women and minorities. The segment on Pierre Curie's death is a tear-jerker, but will generate plenty of respect for Curie's tenacity. For a simulation on the same topic, see link in Activities above to PhET's  Alpha Decay, which contains a very good accompanying lesson plan for high school teachers.

• Physical Sciences K-8 History and Discovery Unit
• Physics First History and Discovery Unit
• Conceptual Physics History and Discovery Unit
• Algebra-Based Physics History and Discovery Unit
• AP/Calculus-Based Physics History and Discovery Unit