An interactive applet and associated web page that provide step-by-step animated instructions on how to construct the incenter of a triangle. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

An interactive applet and associated web page that provide step-by-step instructions on how to find the centroid of a triangle using only a compass and straightedge. The method used involves constructing two of the triangle's medians. The centroid is where they intersect. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

An interactive applet and associated web page that provide step-by-step instructions on how to find a median of a triangle using only a compass and straightedge. The method used involves bisecting one side, then drawing a line from this midpoint to the opposite vertex. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

An interactive applet and associated web page that provide step-by-step instructions on how to construct the orthocenter of a triangle using only a compass and straightedge. The method used involves constructing two altitudes of the triangle, which intersect at the orthocenter. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

An interactive applet and associated web page that provide step-by-step instructions on how to copy a line segment using only a compass and straightedge. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

An interactive applet and associated web page that provide step-by-step instructions on how to divide a line segment into any number of equal parts, using only a compass and straightedge. The applet starts with a given line segment and ends with that segment divided into n parts. In the applet n=5, but the construction works for any n. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. The text on the page has printable step-by-step instructions. 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.

The purpose of this lesson is to learn about the radius and diameter of a circle, as well as how to draw accurate circles using a compass.

Included is a YouTube video to support Grade 7 Blended Learning Math - Unit 4.1: Circles and Area - Investigating Circles.

An interactive applet and associated web page that provide step-by-step instructions on how to find the center of a circle using only a compass and straightedge. The method used involves constructing the perpendicular bisectors of two random chords. The bisectors intersect at the center of the circle. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

Generate electricity with a bar magnet! Discover the physics behind the phenomena by exploring magnets and how you can use them to make a bulb light.

In this lesson, students learn how to determine location by triangulation. We describe the process of triangulation and practice finding your location on a worksheet, in the classroom, and outdoors.

An interactive applet and associated web page that provide step-by-step animated instructions on how to construct an isosceles triangle with given base and altitude using only a compass and straightedge. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

An interactive applet and associated web page that provide step-by-step animated instructions on how to construct an isosceles triangle with given sides using only a compass and straightedge. The animation can be run either continuously like a video, or single stepped to allow classroom discussion and thought between steps. 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.

Ever wonder how a compass worked to point you to the Arctic? Explore the interactions between a compass and bar magnet, and then add the earth and find the surprising answer! Vary the magnet's strength, and see how things change both inside and outside. Use the field meter to measure how the magnetic field changes.

Students complete a series of six short investigations involving magnets to learn more about their properties. Students also discuss engineering uses for magnets and brainstorm examples of magnets in use in their everyday lives.

Students measure the relative intensity of a magnetic field as a function of distance. They place a permanent magnet selected distances from a compass, measure the deflection, and use the gathered data to compute the relative magnetic field strength. Based on their findings, students create mathematical models and use the models to calculate the field strength at the edge of the magnet. They use the periodic table to predict magnetism. Finally, students create posters to communicate the details their findings. This activity guides students to think more deeply about magnetism and the modeling of fields while practicing data collection and analysis. An equations handout and two grading rubrics are provided.

Explore the interactions between a compass and bar magnet. Discover how you can use a battery and wire to make a magnet! Can you make it a stronger magnet? Can you make the magnetic field reverse?

Students create and use their own simple compasses, which are each made from a bowl of water, strong magnet, stick pin and Styrofoam peanuts. They learn how compasses work and about cardinal directions. They come to understand that the Earth's magnetic field has both horizontal and vertical components.

In this unit, students learn the very basics of navigation, including the different kinds of navigation and their purposes. The concepts of relative and absolute location, latitude, longitude and cardinal directions are explored, as well as the use and principles of maps and a compass. Students discover the history of navigation and learn the importance of math and how it ties into navigational techniques. Understanding how trilateration can determine one's location leads to a lesson on the global positioning system and how to use a GPS receiver. The unit concludes with an overview of orbits and spacecraft trajectories from Earth to other planets.

Maps are designed to allow people to travel to a new location without a guide to show the way. They tell us information about areas to which we may or may not have ever been. There are many types of maps available for both recreational and professional use. A navigator uses a nautical map, while an engineer might use a surveyor's map. Maps are created by cartographers, and they can be very specific or very general, depending on their intended use. The focus of this lesson is on how to read and use topographical maps. Students will also learn to identify the common features of a map. Through the associated activities, students will learn how to use a compass to find bearing to an object on a map and in the classroom.

In this activity, students will learn how to read a topographical map and how to triangulate with just a map. True triangulation requires both a map and compass, but to simplify the activity and make it possible indoors, the compass information is given. Students will practice converting a compass measurement to a protractor measurement, as well as reverse a bearing direction (i.e., if they know a tree's bearing is 100 degrees from you, they can determine what bearing they are from the tree). Students will use the accompanying worksheets to take a bearing of certain landmarks and then start at those landmarks to work backwards to figure out where they are.