Stare at one color—but see another. You see color when receptor cells (called cones) in your eye’s retina are stimulated by light. There are three types of cones, and each is sensitive to a particular color range. If one or more of the three types of cones adapts to a stimulus because of long exposure, it responds less strongly than it normally would.

Students read news reports and first-person accounts to imagine what it would be like to be in a blackout in a large city. They follow news reports as if the event were unfolding in real-time and keep weblogs or journals of their experience as they imagine it, taking on different roles of people who live in the city or commute there to work. They use their journal accounts to create a play or screenplay that depicts what the August 2003 blackout was like for the people in the U.S. and Canada who experienced it. Although this activity is geared towards fifth-grade and older students, it could be easily adapted for younger students.

Rockets need a lot of thrust to get into space. In this lesson, students learn how rocket thrust is generated with propellant. The two types of propellants are discussed and relation to their use on rockets is investigated. Students learn why engineers need to know the different properties of propellants.

Students are introduced to our Sun as they explore its composition, what is happening inside it, its relationship to our planet (our energy source), and the ways engineers help us learn about it.

The eye’s retina receives and reacts to incoming light and sends signals to the brain, allowing you to see. One part of the retina, however, doesn't give you visual information—this is your eye’s “blind spot.”

Students will make a proportional model of blood out of red gelatin, a plastic bag, and rice. They will learn about the different components that make up blood and will investigate what happens when the arteries and veins experience buildup from cholesterol. They will then work in pairs to brainstorm ways to clean our clogged arteries.

This activity provides instructions for using a flashlight and aquarium (or other container of water) to explain why the sky is blue and sunsets are red. When the white light from the sun shines through the earth's atmosphere, it collides with gas molecules with the blue light scattering more than the other colors, leaving a dominant yellow-orange hue to the transmitted light. The scattered light makes the sky blue; the transmitted light makes the sunset reddish orange. The section entitled What's Going On? explains this phenomena.

Los estudiantes diseñan, construyen y prueban vehículos de carreras hechos de bobinas de manualidades.

Students design and build devices to protect and accurately deliver dropped eggs. The devices and their contents represent care packages that must be safely delivered to people in a disaster area with no road access. Similar to engineering design teams, students design their devices using a number of requirements and constraints such as limited supplies and time. The activity emphasizes the change from potential energy to kinetic energy of the devices and their contents and the energy transfer that occurs on impact. Students enjoy this competitive challenge as they attain a deeper understanding of mechanical energy concepts.

In this optics activity, learners examine how polarized light can reveal stress patterns in clear plastic. Learners place a fork between two pieces of polarizing material and induce stress by squeezing the tines together. Learners will observe the colored stress pattern in the image of the plastic that is projected onto a screen using an overhead projector. Learners rotate one of the polarizing filters to explore which orientations give the most dramatic color effects. This activity can be related to bones, as bones develop stress patterns from the loads imposed upon them every day.

Experiment with rocket designs and a PVC launcher to discover how high—and how far—you can make your rockets go.

Here’s a new “spin” on an old toy. In this modern adaptation of a classic toy—the spool racer—a plastic water bottle is propelled by energy stored in a wound-up rubber band.

Watch water boil at room temperature. The temperature at which water boils depends on pressure. You can demonstrate this by dramatically lowering the pressure on a water-filled plastic syringe at room temperature.

Students learn about the similarities between the human brain and its engineering counterpart, the computer. Since students work with computers routinely, this comparison strengthens their understanding of both how the brain works and how it parallels that of a computer. Students are also introduced to the "stimulus-sensor-coordinator-effector-response" framework for understanding human and robot actions.

Construct a protein through cereal additions. Model the central dogma of molecular biology by constructing a colorful chain using a simple code (and some delicious cereal).

Students learn about and experiment with the concept of surface tension. How can a paper clip "float" on top of water? How can a paper boat be powered by soap in water? How do water striders "walk" on top of water? Why do engineers care about surface tension? Students answer these questions as they investigate surface tension and surfactants.

Students are introduced to the respiratory system, the lungs and air. They learn about how the lungs and diaphragm work, how air pollution affects lungs and respiratory functions, some widespread respiratory problems, and how engineers help us stay healthy by designing machines and medicines that support respiratory health and function.

In this activity, learners observe as soap bubbles float on a cushion of carbon dioxide gas. Learners blow bubbles into an aquarium filled with a slab of dry ice. Learners will be amazed as the bubbles hover on the denser layer of carbon dioxide gas, then begin to expand and sink before freezing on the dry ice. Use this activity to discuss sublimation, density, and osmosis as well as principles of buoyancy, semipermeability, and interference.

Create giant bubbles! Bubbles are fascinating. What gives them their shape? What makes them break or last? What causes the colors and patterns in the soap film, and why do they change?

Students learn a simple technique for quantifying the amount of photosynthesis that occurs in a given period of time, using a common water plant (Elodea). They can use this technique to compare the amounts of photosynthesis that occur under conditions of low and high light levels. Before they begin the experiment, however, students must come up with a well-worded hypothesis to be tested. After running the experiment, students pool their data to get a large sample size, determine the measures of central tendency of the class data, and then graph and interpret the results.