How might Earth's temperature change in the future? Use this model to explore how changing human emissions of greenhouse gases might affect the temperature. The model incorporates positive and negative feedback loops. Ice cover and cloud cover change in response to the level of water vapor and temperature in the model.

Learn about exponential functions by graphing various equations representing exponential growth and decay. Graph these functions by connecting ordered pairs on x-y axes.

Students learn to graph the equation of a quadratic function using the coordinates of the vertex of a parabola and its x-intercepts. After completing this activity, students will be able to graph a parabola using a vertex and x-intercepts, identify the vertex of a parabola from a quadratic function in standard form and identify the x-intercepts of a quadratic function in standard form.

Build your own miniature "greenhouse" out of a plastic container and plastic wrap, and fill it with different things such as dirt and sand to observe the effect this has on temperature. Monitor the temperature using temperature probes and digitally plot the data on the graphs provided in the activity.

Explore how the Earth's atmosphere affects the energy balance between incoming and outgoing radiation. Using an interactive model, adjust realistic parameters such as how many clouds are present or how much carbon dioxide is in the air, and watch how these factors affect the global temperature.

Make your own miniature greenhouse and measure the light levels at different "times of day"--modeled by changing the angle of a lamp on the greenhouse--using a light sensor. Next, investigate the temperature in your greenhouse with and without a cover. Learn how a greenhouse works and how you can regulate the temperature in your model greenhouse.

This model shows how the size of an object affects how much heat energy it holds and hence how much is needed to heat it up or cool it down. You can explore this by watching the heat transfer between two objects with different sizes and different temperatures.

This model shows how specific heat of an object determines how much heat energy it holds and hence how much is needed to heat it up or cool it down. You can explore this by watching the heat transfer between two objects with different specific heats and different temperatures.

Discover how electricity can be converted into other forms of energy such as light and heat. Connect resistors and holiday light bulbs to simple circuits and monitor the temperature over time. Investigate the differences in temperature between the circuit with the resistor and the circuit using the bulb.

Explore how heat transfers within a home through convection and how this process is affected by the state of the home's windows and wind outside. Both the state of the windows (open or closed) and presence of wind will affect this process. Convection is a specific form of heat transfer where heated air or fluid becomes lighter and rises above unheated air or fluid.

Learn how the code on a strand of DNA can be used to make a protein.

Being able to control the movement of electrons is fundamental for making all electronic devices work. Discover how electric and magnetic fields can be used to move electrons around. Begin by exploring the relationship between electric forces and charges with vectors. Then, learn about electron fields. Finally, test your knowledge in a fun "Electron Shooting" game!

Use the Sound Grapher to create visualizations of sound and learn about the frequency, wavelength, amplitude and velocity of sound waves.

In this investigation, students will learn how non-polar interactions in combination with polar interactions they learned about in the previous unit effect shape of biological molecules and their function. This investigation builds towards PE HS-PS3-5 and PE HS-LS1-6.

This investigation focuses on how electric forces and energy are connected to molecules. Students will explore various simulations to build their understanding of the relationships among electric forces, energy, and the relative distance of two atoms. They will also explain the energy transfers that occur when molecules form and break using the concept of conservation of energy (developed in previous investigations). This investigation builds towards NGSS PEs MS-PS1-1 and HS-PS1-4.

Students will build upon the model of atomic structure that they developed in the previous investigation. In addition, they will explore the forces involved in maintaining an atom's structure and the effect that introduction into an electric field has on electron distribution. Students will extend their conceptual model of electrostatic interactions to include 1) electron transfer as the mechanism for how an object becomes charged and 2) shifting electron distribution to explain how neutral objects can be attracted to both positively and negatively charged objects. This investigation helps build toward NGSS PE(s): HS-PS1-1 and HS-PS1-3.

In this unit, students will explore the issue of ocean acidification by investigating the effects of increasing carbon dioxide concentrations in air and water, researching the impacts of acidity on living organisms, and developing and revising models of how these components interact. By the end of the unit, models will be used to support student explanations of ocean acidification and to explore and test ideas for decreasing its environmental impact upon Earth's oceans and the organisms that live there. This unit builds toward NGSS PE's: MS-LS2-3 and MS-ESS2-1.

Students will use the Hurricane Explorer model to explain and predict how the path and strength of a hurricane can change due to sea surface temperature, surrounding atmospheric pressure systems, and proximity to land. Students also investigate real-world case studies to consider and articulate factors that influence the risk and impact of hurricanes including scientific factors (winds, flooding) and social factors (people and infrastructure) on a local and regional scale. Finally, students will explore the effect of rising global temperatures on hurricanes and be able to answer the guiding question: How will hurricane risks and impacts change over the next 100 years?

Horizontal drilling and hydraulic fracturing are used to produce oil and natural gas from non-porous rock formations. Use this model to explore how such wells are drilled and fractured to release methane from a layer of shale. Like every energy-extraction process, there is the potential for contamination. Use the model to explore how contamination of aquifers might happen during the hydraulic fracturing process.

Explore the polar molecule interactions known as hydrogen bonds. Despite the "bond" name, hydrogen bonds are a special type of dipole-dipole interaction. Hydrogen bonds between two molecules (or within portions of a larger molecule) when hydrogen atoms bonded to highly electronegative atoms (such as nitrogen, oxygen, or fluorine) interact with electronegative portions of a different molecule or within the same molecule. Hydrogen bonds are particularly important in stabilizing large macromolecules, such as proteins and DNA.