Lesson Idea

4 Scientific Articles for Physical Science

We’ve put together this collection of 4 scientific articles aligned with 8th- and 9th-grade Physical Science curriculum, sometimes called Integrated Physics and Chemistry. Below we present four common units for these courses, and a related article selected from our collection.

Each article is adapted from an academic research paper published in a peer-reviewed journal, re-written for students, and reviewed by the researcher. Each contains an introductory video as well as questions to assess the students’ understanding.

A. Matter and Atomic Structure

Atoms: Protons, neutrons, electrons, and isotopes.
Periodic Table: Organizing elements by properties and reactivity.
Bonding: Ionic vs. Covalent bonding and naming compounds.
States of Matter: Solids, liquids, gases, and phase changes (heating curves).
Solutions: Acids, bases, and pH scales.

What can tusks tell us about the lives of mastodons?

Abstract: Did you know that tusks are enormous teeth? Many animals have them, but the biggest ones belong to elephants and their relatives, including mastodons. Mastodons are now extinct, but paleontologists can use fossil tusks to study the lives of these ancient giants. For our study, we analyzed the right tusk of a male mastodon found in 1998. We also analyzed two chemical elements preserved in the tusks: oxygen and strontium. Using different forms of these elements (called isotopes), we tracked the season when a particular layer of tusk was grown, as well as where he grew it. We learned that he traveled long distances to mate with females. He also had fights with other mastodons and even died during his final battle!

Key term: extinction, fossils, migration, paleontology
Scientific figures: map, pictograph
Scientific methods: data reconstruction, mass spectrometry, proxy data, representative sampling, scientific modeling
Additional resources: Audio Edition (English)

B. Motion, Forces, and Energy

Newton’s Laws: Inertia, and action/reaction pairs.
Motion: Calculating speed, velocity, and acceleration.
Energy: Potential vs. Kinetic energy and the Law of Conservation of Energy.
Work & Machines: Simple machines and mechanical advantage.

Can we use bacteria to make renewable rocket fuel?

Abstract: NASA’s space shuttle has to reach speeds of almost 18,000 miles per hour (29,000 kilometers per hour) in only 8.5 minutes. That’s necessary for it to reach outer space. That’s 300 times faster than a car traveling at 60 mph (97 km/h)! To reach these speeds, rockets need particularly high-energy fuels. It’s the same for airplanes and cargo ships, too. At the moment, these high-energy fuels are made using petroleum – a fossil fuel, and the leading cause of global climate change. So, there’s an urgent need for scientists to develop more sustainable high-energy fuels. We explored whether bacteria could make molecules we could turn into high-energy biofuels. We looked into bacterial DNA and used clever chemistry to produce new biofuels using Streptomyces bacteria. These “POP biofuels” seem to be even better (higher energy) than the current petroleum-made rocket fuels!

Key terms: aviation, biotechnology, climate change, fuel, genetics, microbiology, renewable energy, space travel
Scientific figures: bar graph, pictograph
Scientific method: experiment, gene editing, PCR (polymerase chain reaction)
Additional resources: Available in 2 reading levels. Also available in Spanish. Audio Edition (English, Spanish).

C. Waves and Electromagnetic Radiation

Wave Properties: Wavelength, frequency, and amplitude.
Light & Sound: Reflection, refraction, and the electromagnetic spectrum.

Why do ducklings swim in a line behind their mother?

Abstract: Have you ever seen baby ducks or geese swimming in line behind their mother? They’re so cute! But why do they do that? Is it to keep everyone organized and safe? Or is it to make swimming easier for the babies? We wanted to figure out how swimming in a line benefits the ducklings. We hypothesized that this formation saves the ducklings energy. We created a mathematical model to test our hypothesis. We realized that the most energy-efficient place for them to swim is behind their mother. And if they swim at specific positions, the waves created by their mother or passed along by the other ducklings propel them forward. This saves lots of energy!

Key terms: animal behavior, birds, mother, waves
Scientific figures: bar graph
Scientific method: scientific modeling
Additional resources: Available in 2 reading levels. Audio Edition (English). Ask-A-Scientist podcast episode (link) with the original researcher.

D. Electricity and Magnetism

Circuits: Series vs. parallel circuits.
Electromagnetism: How motors and generators work using magnets and wires.

What can you do with a microscopic robot?

Abstract: Can you imagine a robot so small that you can’t even see it without a microscope? No, it’s not science fiction! Microscopic robots, or microbots, are tiny machines that are about the same size as a red blood cell. That’s only a few millionths of a meter across, about a tenth of a hair’s diameter. Making a robot this small is hard. Controlling a microbot is especially challenging! We developed a new type of microbot that can be controlled remotely using an electromagnet. The basic shape of the robot is simple. They have two sides and bend in the middle like an inchworm. They are covered in special, super tiny magnets. By adjusting a magnetic field, we can make microbots walk, swim, and fold themselves up like origami! Their tiny size even lets them change how light bounces off a surface. We think these microbots have a lot of potential!

Key terms: engineering, robotics
Scientific figures: pictograph
Scientific method: experiment
Additional resources: Available in Spanish. Audio Edition (English). Lesson Idea video (link) for hands-on extension.