# 8th Grade Resources

## Classifying Triangles by Angles

(8th grade....probably. Not explicitly covered in Indiana CCR Standards) An Open Middle-style approach to Converse to the Pythagorean Theorem. Drag the digits to the boxes to create three side lengths, then examine the angles that are created. Attempt to create acute, obtuse, and even right (yes...it is possible) triangles. ## Distance Guesser

Designed to connect the distance formula to the Pythagorean Theorem. Start by guessing the distance between two points on the coordinate plane. Then click on "Help" as more information is slowly added. ## Dynamic Correlation

See how the different points are affecting the correlation and regression line. Click on points to temporarily remove them from the data set. ## Equations of Lines

Adjust the line(s) with sliders, either in slope-intercept (y=mx+b) or standard (Ax+By=C) form (or both). Use this to develop understanding of how the parameters affect the graph of the line, or to examine the relationship between the two forms of the line. ## Function Machine

A random function (or "rule") is generated based on the sliders. Send the numbers through the machine to figure out what the rule is. Click on the boxes to see the rule in equation or word form. Alternatively, show the rule then predict the outputs before sending the number through. ## Graphing in Point-Slope and Slope-Intercept Forms

Click on two points to draw the line matching the given information. You have two chances to draw the line, after which the answer will be given.  ## How Many Solutions?

This uses a graphing approach to solving a linear equation in one variable with 0, 1, or infinitely many solutions. The goal is for students to notice patterns in the relationship between coefficients/constants in each expression. ## Linear Equation Guesser

Here's what I was picturing: Everyone in the class writes down an equation. Collect several to put on the board, then click "More info." As information is slowly revealed about the line, which equations are still viable? How could we revise those that aren't? ## Make a Linear Function

Drag the numbers to the table to create points. Can you make a line? What patterns can we notice about the relationship between x and y? ## Move the Number

This activity is meant to develop flexible, creative thinking about numbers and operations. Your goal is to move a from a starting number to a target number, but there are many ways to do this! Adjust the sliders to control the bounds of the numbers involved. ## Similar Triangles

Starting with a pre-image, draws the image for scale factor of your choosing. Click on the sides to show/hide their lengths. ## Slope Guesser

A random line is generated and displayed. Guess the slope, then refine that guess as more information is provided. The final step is to see how the slope is calculated by selecting points on the line. ## Solving a Linear Equation on the Number Line

This activity is meant to give students a more concrete understanding of the steps involved in solving a linear equation of the form ax + b = c (where a, b, c can be any numbers - positive or negative). After you enter your equation, use the properties of equality to solve it, and you'll see the resulting action on the number line. Click "Show solution" at any point in the process. ## Transformation Practice

The image is generated by a random transformation. Determine the type of transformation and the specific mapping. ## Write a Linear Equation

Select the options for how you'll receive information about a linear equation (it will be randomly selected and generated). Then type in the equation and see if you're right. 