## Difference Trains

Build your own difference train with one, two or three difference between blocks. Think about your reasoning as you work.

## The Distance Formula

Plot points on a graph. Use the Pythagorean theorem to calculate the distance between them.

## Division with Manipulatives

Area models offer a visual representation of mathematical operations. Use these models to perform multi-digit division.

## Drawing a Box Plot

Learn how to represent the Five-Number Summary graphically using a box plot.

## Equivalent Expressions

Determine if nine mathematical expressions are equivalent to 20. Then match the equivalent expressions to corresponding word problems.

## Eric the Sheep

One way to solve a complicated problem is to solve a smaller version of the same problem. Without working out the larger problem, predict how many sheep will get shorn before impatient Eric, who is sneaking up in line little by little.

## Even Data Sets

How do you find the median for an even numbers of noodles? Learn how in this three-noodle summary of twelve noodles.

## Exploring Zero and Infinity on a Graph

Explore the number line and its elements through a graphic representation of an equation. Move along the curve of the graph of xy=12 to see how the values change as you vary x or y and consider what happens for negative values of x and y.

## Factors

Explore the factors of numbers 2 to 36. Show how many factors each number has and identify which one are prime.

## Finding the Area of Dot-Paper Shapes

Practice two different methods to calculate the area of complex shapes. As you work, think about how you are approaching it, what difficulties you are encountering, and how you would communicate your thinking to others.

## Fitting Lines to Data

For a given set of data points, the line that minimizes the sum of the squared errors is the least squares line. Find the least squares line that best represents the height and foot length of 17 people in a scatter plot.

## Five Noodle Summary

The Five-Number Summary divides ordered numeric data into four groups with each group having the same number of data values. You will create a five-noodle summary for two different sets of noodles.

## Frequency Bar Graphs

Line plots are good for small amounts of data while frequency bar graphs are better for large amounts. Observe how to transition from line plot to frequency bar graph.

## From Corner to Corner

Measure the lengths and diagonals of three squares with a ruler. Look over your measurements and try to come up with a rule of thumb for estimating the length of a diagonal if you know the length of a side.

## Geo-Logo

Enter commands to direct your drawing tool to create different shapes. Reflect on the relationship between interior, exterior and central angles.

## Guess My Button

Practice classification/pattern recognition skills by guessing which button out of sixteen the computer has chosen. Go through a series of online questions about the buttons that differ in size, color, shape and number of holes to determine the answer.

## Guess My Rule

Someone makes up a mystery algorithm and keeps it secret. With the help of the function machine, try to discover the algorithm with as few guesses as possible.

## Histogram

Review the transitions between various graphical representations of data and discuss the advantages of a histogram have over a stem and leaf plot. Also consider the disadvantages of a histogram.

## How Long is a Minute?

Try to judge when you think a minute has passed without counting in your head or watching a clock. Use the online stopwatch to record your guesses, get some friends to guess as well and try to come up with reasons for the variations in responses.

## How Many Valentines?

How many valentines are exchanged if each of five friends gives a valentine to each of their other friends? Reflect on your solution, compare it with some others listed, and think about how you would solve a similar problem for more people.