Created by the Concord Consortium, the Molecular Workbench is "a modeling tool for designing and conducting computational experiments across science." First-time visitors can check out one of the Featured Simulations to get started. The homepage contains a number of curriculum modules which deal with chemical bonding, semiconductors, and diffusion. Visitors can learn how to create their own simulations via the online manual, which is available here as well. The Articles area is quite helpful, as it contains full-text pieces on nanoscience education, quantum chemistry, and a primer on how transistors work. A good way to look over all of the offerings here is to click on the Showcase area. Here visitors can view the Featured simulations, or look through one of five topical sections, which include Biotech and Nanotechnology. Visitors will need to install the free Molecular Workbench software, which is available for Windows, Linux, and Mac.

Study the motion of a toy car on a ramp and use motion sensors to digitally graph the position data and then analyze it. Make predictions about what the graphs will look like, and consider what the corresponding velocity graphs would look like.

What do plants eat? This unit explores plants and how they make food.

Many factors influence the success and survival rate of a population of living things. Explore several factors that can determine the survival of a population of sheep in this NetLogo model. Start with a model of unlimited grass available to the sheep and watch what happens to the sheep population! Next try to keep the population under control by removing sheep periodically. Change the birthrate, grass regrowth rate, and the amount of energy rabbits get from the grass to keep a stable population.

Delve into a microscopic world working with models that show how electron waves can tunnel through certain types of barriers. Learn about the novel devices and apparatuses that have been invented using this concept. Discover how tunneling makes it possible for computers to run faster and for scientists to look more deeply into the microscopic world.

How does energy flow in and out of our atmosphere? Explore how solar and infrared radiation enters and exits the atmosphere with an interactive model. Control the amounts of carbon dioxide and clouds present in the model and learn how these factors can influence global temperature. Record results using snapshots of the model in the virtual lab notebook where you can annotate your observations.

Measure relative humidity in the air using a simple device made of a temperature sensor, a plastic bottle, and some clay. Electronically plot the data you collect on graphs to analyze and learn from it. Experiment with different materials and different room temperatures in order to explore what affects humidity.

Use a virtual scanning tunneling microscope (STM) to observe electron behavior in an atomic-scale world. Walk through the principles of this technology step-by-step. First learn how the STM works. Then try it yourself! Use a virtual STM to manipulate individual atoms by scanning for, picking up, and moving electrons. Finally, explore the advantages and disadvantages of the two modes of an STM: the constant-height mode and the constant-current mode.

Explore your own straight-line motion using a motion sensor to generate distance versus time graphs of your own motion. Learn how changes in speed and direction affect the graph, and gain an understanding of how motion can be represented on a graph.

Semiconductors are the materials that make modern electronics work. Learn about the basic properties of intrinsic and extrinsic or 'doped' semiconductors with several visualizations. Turn a silicon crystal into an insulator or a conductor, create a depletion region between semiconductors, and explore probability waves of an electron in this interactive activity.

Investigate what makes something soluble by exploring the effects of intermolecular attractions and what properties are necessary in a solution to overcome them. Interactive models simulate the process of dissolution, allowing you to experiment with how external factors, such as heat, can affect a substance's solubility.

What happens when an excited atom emits a photon? What can we deduce about that atom based on the photons it can emit? A series of interactive models allows you to examine how the energy levels the electrons of an atom occupy affect the types of photons that can be emitted. Use a digital spectrometer to record which wavelengths certain atoms will emit, and then use this knowledge to compare and identify types of atoms. Students will be abe to:

Transistors are the building blocks of modern electronic devices. Your cell phones, iPods, and computers all depend on them to operate. Thanks to today's microfabrication technology, transistors can be made very tiny and be massively produced. You are probably using billions of them while working with this activity now--as of 2006, a dual-core Intel microprocessor contains 1.7 billion transistors. The field effect transistor is the most common type of transistor. So we will focus on it in this activity.

All cells, organs and tissues of a living organism are built of molecules. Some of them are small, made from only a few atoms. There is, however, a special class of molecules that make up and play critical roles in living cells. These molecules can consist of many thousands to millions of atoms. They are referred to as macromolecules (or large biomolecules).

Windmills have been used for hundreds of years to collect energy from the wind in order to pump water, grind grain, and more recently generate electricity. There are many possible designs for the blades of a wind generator and engineers are always trying new ones. Design and test your own wind generator, then try to improve it by running a small electric motor connected to a voltage sensor.