In the everyday electrical devices we use calculators, remote controls and cell phones a voltage source such as a battery is required to close the circuit and operate the device. In this hands-on activity, students use batteries, wires, small light bulbs and light bulb holders to learn the difference between an open circuit and a closed circuit, and understand that electric current only occurs in a closed circuit.

In a multi-week experiment, students monitor the core temperatures of two compost piles, one control and one tended, to see how air and water affect microbial activity. They daily aerate and wet the "treated" pile and collect 4-6 weeks' worth of daily temperature readings. Once the experiment is concluded, students plot and analyze their data to compare the behavior of the two piles. They find that the treated pile becomes hotter, an indication that more microbes are active and releasing heat. Through this activity, students see that microbes play a role in composting and how composting can be used as a carbon management process.

Students explore the concept of biodegradability by building and observing model landfills to test the decomposition of samples of everyday garbage items. They collect and record experiment observations over five days, seeing for themselves what happens to trash when it is thrown "away" in a landfill environment. This shows them the difference between biodegradable and non-biodegradable and serves to introduce them to the idea of composting. Students also learn about the role of engineering in solid waste management.

The first video in Lesson 02: Computer Hardware. This video takes a quick look at the categories of computer hardware: processing, storage, input, and output.

The computer program's simulation of a Sonoran desert community should ultimately strengthen the student's comprehension of what is required for a natural ecosystem to sustain itself (remain in balance). This computer simulation program has great flexibility. It allows the student to manipulate the population numbers of five Sonoran Desert species. A species natural history attachment provides vital information for the students to familiarize themselves with each species' behaviors, its niche and food resource needs. The program includes two producers, the Saguaro cactus and the Ironwood Tree. It also includes 3 consumers, but their interactions both toward the producers and each other differ. The community's ability to remain in balance and sustain all five species so that none die out rests on the student's assessment skills enabling him to correctly identify these dependencies. The student learns by trial and error as he continues to fine tune the ecosystem that he maintains stewardship of.

Students investigate the property dependence between concentrations and boiling point. In section 1, students first investigate the boiling point of various liquid solutions. In section 2, they analyze data collected by the entire class to generate two boiling point curves, one for salt solutions and one for sugar solutions. Finally, in section 3, students use the data they have analyzed to determine how to create a solution that has a particular boiling point and is a cost-effective design.

Students learn how the total solar irradiance hitting a photovoltaic (PV) panel can be increased through the use of a concentrating device, such as a reflector or lens. This is the final lesson in the Photovoltaic Efficiency unit and is intended to accompany a fun design project (see the associated Concentrating on the Sun with PVs activity) to wrap up the unit. However, it can be completed independently of the other unit lessons and activities.

Students design, build and test reflectors to measure the effect of solar reflectance on the efficiency of solar PV panels. They use a small PV panel, a multimeter, cardboard and foil to build and test their reflectors in preparation for a class competition. Then they graph and discuss their results with the class. Complete this activity as part of the Photovoltaic Efficiency unit and in conjunction with the Concentrated Solar Power lesson.

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.

In this interactive activity, learners build computer models of atoms by adding or removing electrons, protons, and neutrons. It presents the orbital model of an atom: a nucleus consisting of protons and neutrons with electrons surrounding it in regions of high probability called orbitals. Guided tasks are provided, such as constructing a lithium atom and a carbon-12 atom in the fewest possible steps. The activity concludes with a model for building a charged hydrogen atom (an ion). Within each task, students take snapshots of their work product and answer probative questions. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.

Elementary grade students investigate heat transfer in this activity to design and build a solar oven, then test its effectiveness using a temperature sensor. It blends the hands-on activity with digital graphing tools that allow kids to easily plot and share their data. Included in the package are illustrated procedures and extension activities. Note Requirements: This lesson requires a "VernierGo" temperature sensing device, available for ~ $40. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology. The Consortium develops digital learning innovations for science, mathematics, and engineering.

With the help of simple, teacher-led demonstration activities, students learn the basic concepts of heat transfer by means of conduction, convection, and radiation. Students then apply these concepts as they work in teams to solve two problems. One problem requires that they maintain the warm temperature of one soda can filled with water at approximately body temperature, and the other problem is to cause an identical soda can of warm water to cool as much as possible during the same thirty-minute time interval. Students design their solutions using only common, everyday materials. They record the water temperatures in their two soda cans every five minutes, and prepare line graphs in order to visually compare their results to the temperature of an unaltered control can of water.

Students make a simple conductivity tester using a battery and light bulb. They learn the difference between conductors and insulators of electrical energy as they test a variety of materials for their ability to conduct electricity.

Explore how populations change over time in a NetLogo model of sheep and grass. Experiment with the initial number of sheep, the sheep birthrate, the amount of energy sheep gain from the grass, and the rate at which the grass re-grows. Remove sheep that have a particular trait (better teeth) from the population, then watch what happens to the sheep teeth trait in the population as a whole. Consider conflicting selection pressures to make predictions about other instances of natural selection.

Students learn about isometric drawings and practice sketching on triangle-dot paper the shapes they make using multiple simple cubes. They also learn how to use coded plans to envision objects and draw them on triangle-dot paper. A PowerPoint® presentation, worksheet and triangle-dot (isometric) paper printout are provided. This activity is part of a multi-activity series towards improving spatial visualization skills.

Students are introduced to the idea of improving efficiency by examining a setting that is familiar to many teenagers fast food restaurants. More specifically, they learn about the concepts of trade-offs, constraints, increasing efficiency and systems thinking. They consider how to improve efficiency in a struggling restaurant through delegating tasks, restructuring employee responsibilities and revising a floor plan, all while working within limitations and requirements. Finally, students summarize and defend their suggested changes in argumentative essays.