An interactive applet and associated web page that shows how triangles that have two angles and a non-included side the same must be congruent. The applet shows two triangles, one of which can be reshaped by dragging any vertex. The other changes to remain congruent to it and the two angles and non-included side are outlined in bold to show they are the same measure and are the elements being used to prove congruence. The web page describes all this and has links to other related pages. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

Join Simon, Anita, Emily and the rest of Ms. Patel's class as they gain an understanding of how the Earth works as a system while preparing their end of the school year play.

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

We use the derivative to determine the maximum and minimum values of particular functions (e.g. cost, strength, amount of material used in a building, profit, loss, etc.).Differentiation is also used in analysis of finance and economics.

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.

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

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

This learning video is designed to develop critical thinking in students by encouraging them to work from basic principles to solve a puzzling mathematics problem that contains uncertainty. Materials for in-class activities include: a yard stick, a meter stick or a straight branch of a tree; a saw or equivalent to cut the stick; and a blackboard or equivalent. In this video lesson, during in-class sessions between video segments, students will learn among other things: 1) how to generate random numbers; 2) how to deal with probability; and 3) how to construct and draw portions of the X-Y plane that satisfy linear inequalities.

Experiment with conductivity in metals, plastics and photoconductors. See why metals conduct and plastics don't, and why some materials conduct only when you shine a flashlight on them.

Why do objects like wood float in water? Does it depend on size? Create a custom object to explore the effects of mass and volume on density. Can you discover the relationship? Use the scale to measure the mass of an object, then hold the object under water to measure its volume. Can you identify all the mystery objects?

Explore tunneling splitting in double well potentials. This classic problem describes many physical systems, including covalent bonds, Josephson junctions, and two-state systems such as spin 1/2 particles and ammonia molecules.

This learning video introduces students to the world of Fractal Geometry through the use of difference equations. As a prerequisite to this lesson, students would need two years of high school algebra (comfort with single variable equations) and motivation to learn basic complex arithmetic. Ms. Zager has included a complete introductory tutorial on complex arithmetic with homework assignments downloadable here. Also downloadable are some supplemental challenge problems. Time required to complete the core lesson is approximately one hour, and materials needed include a blackboard/whiteboard as well as space for students to work in small groups. During the in-class portions of this interactive lesson, students will brainstorm on the outcome of the chaos game and practice calculating trajectories of different equations.

Learn how friction causes a material to heat up and melt. Rub two objects together and they heat up. When one reaches the melting temperature, particles break free as the material melts away. Arabic Language.

Pump gas molecules to a box and see what happens as you change the volume, add or remove heat, change gravity, and more. Measure the temperature and pressure, and discover how the properties of the gas vary in relation to each other.

This survey chemistry course is designed to introduce students to the world of chemistry. In this course, we will study chemistry from the ground up, learning the basics of the atom and its behavior. We will apply this knowledge to understand the chemical properties of matter and the changes and reactions that take place in all types of matter. Upon successful completion of this course, students will be able to: Define the general term 'chemistry.' Distinguish between the physical and chemical properties of matter. Distinguish between mixtures and pure substances. Describe the arrangement of the periodic table. Perform mathematical operations involving significant figures. Convert measurements into scientific notation. Explain the law of conservation of mass, the law of definite composition, and the law of multiple proportions. Summarize the essential points of Dalton's atomic theory. Define the term 'atom.' Describe electron configurations. Draw Lewis structures for molecules. Name ionic and covalent compounds using the rules for nomenclature of inorganic compounds. Explain the relationship between enthalpy change and a reaction's tendency to occur. (Chemistry 101; See also: Biology 105. Mechanical Engineering 004)

In this hands-on inquiry activity, students will design and construct an apparatus that will permit an egg to survive a nine foot fall. Students are given limited materials, so they must critically think about the design and improvise strategies during the building of the apparatus

This lesson unit is intended to help teachers assess how well students are able to: interpret data and evaluate statistical summaries; and critique someone elseŐs interpretations of data and evaluations of statistical summaries. The lesson also introduces students to the dangers of misapplying simple statistics in real-world contexts, and illustrates some of the common abuses of statistics and charts found in the media.

This learning video addresses a particular problem of selection bias, a statistical bias in which there is an error in choosing the individuals or groups to make broader inferences. Rather than delve into this broad topic via formal statistics, we investigate how it may appear in our everyday lives, sometimes distorting our perceptions of people, places and events, unless we are careful. When people are picked at random from two groups of different sizes, most of those selected usually come from the bigger group. That means we will hear more about the experience of the bigger group than that of the smaller one. This isn't always a bad thing, but it isn't always a good thing either. Because big groups ''speak louder,'' we have to be careful when we write mathematical formulas about what happened in the two groups. We think about this issue in this video, with examples that involve theaters, buses, and lemons. The prerequisite for this video lesson is a familiarity with algebra. It will take about one hour to complete, and the only materials needed are a blackboard and chalk.

Are all atoms of an element the same? How can you tell one isotope from another? Use the sim to learn about isotopes and how abundance relates to the average atomic mass of an element.

This task is closely related to very important material about similarity and ratios in geometry.

Create a laser by pumping the chamber with a photon beam. Manage the energy states of the laser's atoms to control its output.

Create a laser by pumping the chamber with a photon beam. Manage the energy states of the laser's atoms to control its output.

How do microwaves heat up your coffee? Adjust the frequency and amplitude of microwaves. Watch water molecules rotating and bouncing around. View the microwave field as a wave, a single line of vectors, or the entire field.

How did scientists figure out the structure of atoms without looking at them? Try out different models by shooting light at the atom. Check how the prediction of the model matches the experimental results.

Build your own system of heavenly bodies and watch the gravitational ballet. With this orbit simulator, you can set initial positions, velocities, and masses of 2, 3, or 4 bodies, and then see them orbit each other.

Start a chain reaction, or introduce non-radioactive isotopes to prevent one. Control energy production in a nuclear reactor! (Previously part of the Nuclear Physics simulation - now there are separate Alpha Decay and Nuclear Fission sims.)

See how light knocks electrons off a metal target, and recreate the experiment that spawned the field of quantum mechanics.

The goals of the International OER Exchange Pilot project are to: facilitate the development and use of Open Educational Resources (OER) by teachers and students globally, track the development and use of the science learning materials and data collection, especially around climate change study, created in the project through OER Commons, and highlight the process and results through workshops and conference presentations.The broader purpose of the project is to support the international exchange of information and understanding through freely available resources among teachers and students, especially in the area of environmental science and climate change investigation.

Explore the properties of quantum "particles" bound in potential wells. See how the wave functions and probability densities that describe them evolve (or don't evolve) over time.

Learn about different types of radiometric dating, such as carbon dating. Understand how decay and half life work to enable radiometric dating to work. Play a game that tests your ability to match the percentage of the dating element that remains to the age of the object.

Explore what makes a reaction happen by colliding atoms and molecules. Design experiments with different reactions, concentrations, and temperatures. When are reactions reversible? What affects the rate of a reaction?

The topic of photosynthesis is a fundamental concept in biology, chemistry, and earth science. Educational studies have found that despite classroom presentations, most students retain their naive idea that a plant's mass is mostly derived from the soil, and not from the air. To call students' attention to this misconception, at the beginning of this lesson we will provide a surprising experimental result so that students will confront their mental mistake. Next, we will help students better envision photosynthesis by modeling where the atoms come from in this important process that produces food for the planet. This lesson can be completed in 50-60 minutes, with the students working on in-class activities during 20-25 minutes of the lesson. As a prerequisite, students need an introductory lesson on photosynthesis, something that includes the overall chemical equation. If students have already studied the intracellular photosynthetic process in detail, this video can still be very helpful because students often miss the big picture about photosynthesis. Materials needed include red, white and black LEGO bricks (described in downloadable hand-out) or strips of red, white and black paper plus paper clips (directions provided in downloadable hand-out). In addition to class discussions, the major in-class activity of this video involves the students' modeling with LEGO bricks or colored paper where the atoms come from in photosynthesis.

This is a summary and example of my experiences and successes "flipping" my Algebra I classroom in the 2012-13 school year. An example of the materials a student would encounter in a given 24 hour period are included.

How did Rutherford figure out the structure of the atom without being able to see it? Simulate the famous experiment in which he disproved the Plum Pudding model of the atom by observing alpha particles bouncing off atoms and determining that they must have a small core.

Add different salts to water, then watch them dissolve and achieve a dynamic equilibrium with solid precipitate. Compare the number of ions in solution for highly soluble NaCl to other slightly soluble salts. Relate the charges on ions to the number of ions in the formula of a salt. Calculate Ksp values. Arabic Language.

In this activity, learners explore scale by using building cubes to see how changing the length, width, and height of a three-dimensional object affects its surface area and its volume. Learners build bigger and bigger cubes to understand these scaling relationships.

Watch different types of molecules form a solid, liquid, or gas. Add or remove heat and watch the phase change. Change the temperature or volume of a container and see a pressure-temperature diagram respond in real time. Relate the interaction potential to the forces between molecules.

Heat, cool and compress atoms and molecules and watch as they change between solid, liquid and gas phases.

The main objective of this video lesson is to bring the students' attention to the importance of basic and natural sciences in our lives. The lesson will introduce a topic (sustainable energy) that is related mainly to chemistry and is not usually covered directly in a high school curriculum. We hope that this lesson will show students how important and useful the natural and basic sciences are not only for our daily lives, but also for sustainable development. The lesson will present creative and challenging ideas on the topic of alternative energies. It is hoped that students will be inspired by the introduction of these ideas, and that they will develop the confidence to come up with creative ideas themselves. Background for this lesson is based on fundamental concepts in chemistry (mainly), biology, physics and environmental science.

This learning video presents an introduction to graph theory through two fun, puzzle-like problems: ''The Seven Bridges of Konigsberg'' and ''The Chinese Postman Problem''. Any high school student in a college-preparatory math class should be able to participate in this lesson. Materials needed include: pen and paper for the students; if possible, printed-out copies of the graphs and image that are used in the module; and a blackboard or equivalent. During this video lesson, students will learn graph theory by finding a route through a city/town/village without crossing the same path twice. They will also learn to determine the length of the shortest route that covers all the roads in a city/town/village. To achieve these two learning objectives, they will use nodes and arcs to create a graph and represent a real problem.