Watch alpha particles escape from a polonium nucleus, causing radioactive alpha decay. See how random decay times relate to the half life.

In this middle school and high school unit, students engage with 360�� virtual reality tours, authentic Arctic datasets, and app-based labs to construct models and explanations for the unit driving question, "Why might the Arctic be warming twice as fast as the rest of the world?"

Explore the interactions between various combinations of two atoms. Turn on the force arrows to see either the total force acting on the atoms or the individual attractive and repulsive forces. Try the "Adjustable Attraction" atom to see how changing the parameters affects the interaction.

In this activity, students will explore how the Law of Conservation of Energy (the First Law of Thermodynamics) applies to atoms, as well as the implications of heating or cooling a system. This activity focuses on potential energy and kinetic energy as well as energy conservation. The goal is to apply what is learned to both our human scale world and the world of atoms and molecules.

In this experiment, two chemicals that can be found around the house will be mixed within a plastic baggie, and several chemical changes will be observed.

Experiment with a helium balloon, a hot air balloon, or a rigid sphere filled with different gases. Discover what makes some balloons float and others sink.

Why does a balloon stick to your sweater? Rub a balloon on a sweater, then let go of the balloon and it flies over and sticks to the sweater. View the charges in the sweater, balloons, and the wall.

Explore the origin of energy bands in crystals of atoms. The structure of these bands determines how materials conduct electricity.

Look inside a battery to see how it works. Select the battery voltage and little stick figures move charges from one end of the battery to the other. A voltmeter tells you the resulting battery voltage.

Watch beta decay occur for a collection of nuclei or for an individual nucleus.

This is a Biochemistry Pre-test or Review, matching exercise. In the form of a one page Word document. It is the first unit in AP Biology with these terms being used throughout the rest of the year, so it is essential learning for that course.

Bridges come in a wide variety of sizes, shapes, and lengths and are found all over the world. It is important that bridges are strong so they are safe to cross. Design and build a your own model bridge. Test your bridge for strength using a force sensor that measures how hard you pull on your bridge. By observing a graph of the force, determine the amount of force needed to make your bridge collapse.

A bungee jump involves jumping from a tall structure while connected to a large elastic cord. Design a bungee jump that is "safe" for a hard-boiled egg. Create a safety egg harness and connect it to a rubber band, which is your the "bungee cord." Finally, attach your bungee cord to a force sensor to measures the forces that push or pull your egg.

A zip line is a way to glide from one point to another while hanging from a cable. Design and create a zip line that is safe for a hard-boiled egg. After designing a safety egg harness, connect the harness to fishing line or wire connected between two chairs of different heights using a paper clip. Learn to improve your zip line based on data. Attach a motion sensor at the bottom of your zip line and display a graph to show how smooth a ride your egg had!

There are two types of catalysis reactions: homogeneous and heterogeneous. In a homogeneous reaction, the catalyst is in the same phase as the reactants. In a heterogeneous reaction, the catalyst is in a different phase from the reactants. This activity addresses homogeneous catalysis.

This interactive, scaffolded activity allows students to build an atom within the framework of a newer orbital model. It opens with an explanation of why the Bohr model is incorrect and provides an analogy for understanding orbitals that is simple enough for grades 8-9. As the activity progresses, students build atoms and ions by adding or removing protons, electrons, and neutrons. As changes are made, the model displays the atomic number, net charge, and isotope symbol. Try the "Add an Electron" page to build electrons around a boron nucleus and see how electrons align from lower-to-higher energy. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology. The Concord Consortium develops deeply digital learning innovations for science, mathematics, and engineering. The models are all freely accessible. Users may register for additional free access to capture data and store student work products.

This interactive activity helps learners visualize the role of electrons in the formation of ionic and covalent chemical bonds. Students explore different types of chemical bonds by first viewing a single hydrogen atom in an electric field model. Next, students use sliders to change the electronegativity between two atoms -- a model to help them understand why some atoms are attracted. Finally, students experiment in making their own models: non-polar covalent, polar covalent, and ionic bonds. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.

This 90-minute activity features six interactive molecular models to explore the relationships among voltage, current, and resistance. Students start at the atomic level to explore how voltage and resistance affect the flow of electrons. Next, they use a model to investigate how temperature can affect conductivity and resistivity. Finally, they explore how electricity can be converted to other forms of energy. The activity was developed for introductory physics courses, but the first half could be appropriate for physical science and Physics First. The formula for Ohm's Law is introduced, but calculations are not required. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology. The Concord Consortium develops deeply digital learning innovations for science, mathematics, and engineering.

This concept-building activity contains a set of sequenced simulations for investigating how atoms can be excited to give off radiation (photons). Students explore 3-dimensional models to learn about the nature of photons as "wave packets" of light, how photons are emitted, and the connection between an atom's electron configuration and how it absorbs light. Registered users are able to use free data capture tools to take snapshots, drag thumbnails, and submit responses. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.

In this interactive activity, learners explore factors that cause atoms to form (or break) bonds with each other. The first simulation depicts a box containing 12 identical atoms. Using a slider to add heat, students can see the influence of temperature on formation of diatomic bonds. Simulations #2 and #3 introduce learners to reactions involving two types of atoms. Which atom forms a diatomic molecule more easily, and why? The activity concludes as students explore paired atoms (molecules). In this simulation they compare the amount of energy needed to break the molecular bonds to the energy needed to form the bonds. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.