Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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The Rectangle Method

One approach for finding area is to surround the shape with a rectangle, determine the areas of the rectangle and subtract the pieces of the rectangle that are outside the original shape. Use this geoboard to create shapes and determine their areas.

Repeating Decimal Rings

The process of converting fractions to decimals can help clarify the relationship between the two. Investigate the repeating parts that emerge when you expand sevenths and 13ths fractions into decimals.

Representing Different Styles of Data

This activity explores how to interpret different styles of representing data, focusing on data related to the thinning ozone layer.

Running a Function Machine

The connected machine is a single function that takes an input, runs it through the network inside and produces an output. You control a network of function machines along with the input and the operation performed by each machine to solve problems.


Can you judge an object by its shadow? Use your mental rotation skills to determine if a shadow can be produced by a particular shape.

Slicing Solids

A cross section is the face you get when you make one slice through an object. See how many shapes you can make when you cut different cross sections of a cube.

Subdividing Area

To find the area of a shape, surround the shape with a rectangle, determine the areas of the rectangle and subtract the pieces of the rectangle that are outside the original shape. Use this geoboard to create shapes and determine their areas.

Syntax Store

The colors listed in the boxes represent different parts of speech: noun, verb, adjective, adverb, etc. Figure out which colors represent which part of speech and then use the colors to create proper sentences.

Taxicab Treasure Hunt

To find a hidden treasure use taxicab geometry, a special kind of geometry that counts in city blocks. Pick an intersection, ask the computer how far it is to the treasure and get the distance using taxicab geometry.

Testing Your Measurement Bias

There are many sources of variation in data, including random error and bias. Observe the difference between error and bias in this line matching exercise.

Thinking About Slope

Explore the concept of slope. Ask yourself why the slope between pairs of points would change or why it would stay the same.

Three-Noodle Summary

Practice locating the median for odd and even data sets. Consider the information you can glean from a set of data even if you only have Min, Med and Max.

The Towers Problem

Build as many different looking towers as is possible, each exactly four cubes high using two colors of Unifix® Cubes. Convince yourself and others that you have found all possible towers four cubes high and that you have no duplicates.

Transforming a Circle

You can find the areas of different polygons by dissecting the polygons and rearranging the pieces into a recognizable simpler shape. Cut a circle into wedges and fit them together to form a crude parallelogram.

Trigonomic Functions

Use a trigonometry calculator to explore the ratios of sides of a right triangle. Do the sine, cosine and tangent have maximum or minimum values?

Units and Prefixes

Explore some common units and prefixes in the metric system. Then decide which metric units you would use to measure several displayed objects.

Using Hexominos to Manufacture Boxes

Which hexomino net wastes the least amount of paper and yields the most boxes per sheet? Comment on how concepts such as area, spatial visualization and relationships among geometric shapes are all involved in solving this problem.

Variation in Estimates

A computer can perform random sampling and estimation faster than you can. Use the computer to help you estimate a penguin population from computer-selected random samples.

Volume Symbols

Study the names and abbreviations of volume units in both the metric and British systems. Then play a game to see how well you remember them.

Working with the Mean Absolute Deviation (MAD)

The concept of the arithmetic mean and deviation from the mean can be graphically representated as a line plot. You will create a line plot to represent specified allocations of coins.

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