## The Angle Sum of a Triangle

An interactive animation demonstrating the proof of the fact that the sum of internal angles of any triangle is 180º. Click the numbered buttons to observe the steps required for the proof.

http://www.absorblearning.com/media/item.action?quick=eg

For more interactive resources from Absorb Mathematics, visit
http://www.absorblearning.com/media/search.action#search

## Isometric Shapes

Isometric Shape Draw
Use this teaching resource to demonstrate the representation of 3D shapes using isometric paper.

Isometric Shape Exploder
This resource demonstrates isometric shapes and enables classroom discussion about the number of small cubes in each shape. After discussing the shape it can be exploded to show its components. It can also be toggled to rotate. There are 7 isometric shapes to consider.

## Cuboid Exploder

This interactive whiteboard resource is useful for demonstrating the volume of cubes and cuboids.

## Rep-Tiles

Rep-Tiles are tiles of a particular shape such that duplicates of a shape can be combined to form a larger version of the same shape. The website has 7 different Rep-Tiles to choose from.

Instructions
http://www.teacherled.com/2009/01/19/rep-tiles/

Worksheet, so students can solve the puzzles at their desks
http://www.teacherled.com/resources/reptile/reptiles.pdf

## Translation Plotter

Click on one of the shape buttons to the right of the grid to display the corresponding shape in a random position. A set of instructions for translating this shape will also appear in the blue box. Drag and drop the four circular markers to the translated position of the shape’s corners. If they are placed in the correct position the translated shape will be drawn on the screen.

## Angle Properties

A top-notch collection of activities to reinforce some geometry theorems:
* angles on a straight line
* complementary angles
* supplementary angles
* vertically opposite angles
Three thumbs up!

Click on the magnifying glass to fill the screen (or interactive whiteboard)

http://www.mathbuddyonline.com/lessons/math/geometry/angles/pairsofangle...

## Enlargements

There are three parts to this resource:

Introduction to enlargements: This is an ideal resource for introducing pupils to the concept of enlargement and scale factor. .

Enlargements without a centre of enlargement: The resource enables the user to enlarge a given shape by dragging the vertices of a polygon.

Enlargements with a centre of enlargement: This is a very powerful resource that is perfect for exploring the enlargement of shapes using a centre of enlargement.

http://www.ngfl-cymru.org.uk/vtc/ngfl/maths/echalk/enlargement/index.htm

## Transformation Golf

Use your knowledge of transformations on the number plane to put the golf ball into the hole.

http://www.topmarks.co.uk/r.aspx?sid=3814

## Concentration Memory Game

Concentration Memory Game

You can choose to play the game to revise number facts, fraction concepts or fraction-decimal-percent conversions. Very nice implementation!

http://illuminations.nctm.org/ActivityDetail.aspx?ID=73

## Eyeballing Game

In this cool game, you have to move a point to construct a given figure, eg a parallelogram, or an angle bisector. Your distance from the correct point is recorded. At the end your average error is given. There is a Top Ten Scoreboard as well as a Top Score for your computer. Three thumbs up!
http://woodgears.ca/eyeball/index.html