Use a 3D globe to visualize and measure the shortest path between cities. This manipulative shows the great circle route and the great circle distance between a number of cities around the globe. Click and drag to rotate the globe.
To see the rout...e and distance between any two cities on the map, simply click on the red dots representing the two cities. Two routes are shown. The green route is the smaller arc of the great circle containing your two cities. The approximate great circle distance is shown in the box at the upper left corner.
There are more instructions to the right of the manipulative.[more]

Turtle Geometry – Explore numbers, shapes, and logic by programming a turtle to move. There are more instructions on the right side of the Java applet.

Inspector Bloop wants to build a pond for her fish, but her bloops are having trouble fitting together all the pieces! How will she solve this problem? This animated video can be used to introduce a math lesson on tessellations. A teacher could foll...ow the video with a discussion about why the pond pieces did not fit together and how they could be arranged to fit better. ( 1:40)[more]

Using this virtual manipulative you may:
-Display a figure outline
-Move, rotate, and flip "tans" (pieces)
-Change colors
-Reset the workspace
There are instructions to the right of the manipulative.

The Golden Rectangle is a plot created by starting with a rectangle, chopping off successive squares, and drawing quarter circles with a radius equal to the side of the square that was cut.
The center of the spiral is obtained by intersecting a diag...onal of the largest rectangle with a diagonal of the second-largest rectangle.
Using this virtual manipulative you may:
-Start plotting
-Pause the plotter
-Clear the plot
-Turn the outer rectangle
-Hide the inner squares
-Display the spiral center
-Change the size of the outer rectangle
There are more instructions to the right of the manipulative.[more]

This 8:29 video explains the basic concept of trig functions sin, cos, and tan and how to write ratios using these functions and triangle
side lengths. It also explains how to find the trig values using a
calculator and how to find the angle mea...sures if you know a trig value. This is a good basic introduction, but the sound quality is weak and the most important element is the explanation of
SOHCAHTOA as a memory devise for students[more]

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