Hand Span and Foot Length Students collect, organize, graph, and interpret data from measurements of handspan and foot length. 
Understanding Graphs Students will work with graphs and develop an understanding of several graph types. 
A Proportions Activity for Middle School In this activity, students will scale a recipe for trail mix using proportional reasoning. 
Proving the Pythagorean Theorem: A Geometry Activity for Middle School In this activity, students will prove the Pythagorean Theorem and its converse using a proof first published by President James Garfield. The activity is appropriate for grade 8 and covers CCSSM standards 8.EE.1, 8.EE.7b, and 8.G.6. 
Distance and Time Graphs Analyze and interpret distance vs. time graphs. 
Heat It Up
Heat It Up  Reference Sheet
This project entails having students work in small groups to build a solar box to be heated by the sun, tracked by a thermometer. The data is a great starting point for linear models. I have used this project as an opener to the 8th grade and algebra year. Typically, to get a decent set of data, it needs to be a sunny day, so you might be hard struck finding that in middle of the year. However, since it has been a relatively mild winter, you might find a time to try this!

Writing Equations in PointSlope Form
As an alternate to pointslope form, the learner will use slopeintercept form to write the equation of a line. 
A Graphing Look at Rational Numbers
Here is a new representation that uses the xycoordinate graph to show the rational numbers. Since rational numbers are a/b where a and b are integers (with b 0), the graph just has dots at the points (x, y) where both x and y are integers. Then each graph point (x, y) is identified with the rational number y/x. The examples go on to show how to find rational number approximations to square roots that are irrational. by Jim Hirstein

Middle Grades Problem Solving: Figurate Numbers
Students will use patterns to develop recursive and explicit representations for triangular numbers. Extension: Square numbers, pentagonal, etc.

Reading Data from Graphs  Student Sheet
Reading Data from Graphs  Teacher Notes
Lesson Objectives: Students will identify patterns and relationships between variables using information in a graph.
Students will create a table from data in a coordinate graph.
Students will compare patterns of change in a table and graph.

Cylinder Problem
The learner will build a family of cylinders and discover the relation between the dimensions of the generating rectangle and the resulting pair of cylinders. They will then order the cylinders by their volumes and draw conclusions about the relation between the cylinder’s dimensions and its volume. They will calculate the volumes of the family of cylinders with constant area and constant perimeter. 
Irrational Numbers  Wheel of Theodorus Art
This lesson allows students to investigate irrational numbers and how
they are different from rational numbers. Students create a product
that displays irrational numbers. 
Book Page
Numbers
This is an investigation about the total number of pages in a book and
the sum of all the page numbers in a book. 
Building
With Toothpicks
This is an investigation using toothpicks and patterning to explore
perimeter. 
Graphing
Calculator Investigation
This is an activity using graphing calculators to investigate graphs of
linear equations. 
Math
Categories Game
This is a Jeopardylike game to review 7th grade concepts. 
Smarty's
Deli
Students will answer a constructed response question. Students will
then use a rubric to grade the responses and revise their answers. 
Bagging
the Concepts While Covering Your Books
Using a brown paper bag to cover a student's math book provides a rich
mathematical environment for a review of geometric terminology. 
Dr.
Olivo's Hairy Eyeball Theory
Students will use scatter plots to analyze data and look at the
relationship in how long a student can hold their eyes open and the
length of their hair. 
Is
There Another Way?
Students can quickly find prime factorization, GCF, LCM and simplify
fractions using Upside Down Division.

Maze
for a Grade
This activity is designed to have students compare their experimental
probabililty to the theoretical probability. 
Mixing
it Up with Conditional Probability
Students will collect their own data on the color proportions of plain
M&M’s and Skittles for this activity. 
PaperRockScissors
Explore the relationship between experimental and theoretical
probabilities by introducing the concept of a fair game. 
Missing
Values Part 1
Missing
Values Part 2 
Native
American Designs Project
Native
American Designs Powerpoint 
Monty's
Dilemma 
Montana
Math Problem 
Monty
Carlo Birthday Problem 
Classifying
Number Sets 
Around
or All Over 
Car
Speed Project 
The
Perplexing King Arthur Problem 