• ## The Lowdown | Exploring Changing Obesity Rates Through Ratios and Graphs

In these KQED Lowdown infographics, explore how adult obesity rates in the United States, as measured by body mass index (BMI), have dramatically changed in the past half-century. A circular graph and a pictograph depict data by decade, indicating which parts of the population were not overweight, overweight, obese, and extremely obese according to BMI. In the accompanying classroom activity, students develop an understanding of the ratios and proportional relationships by examining numerical data found in the graphs and creating their own bar graphs. This resource is part of the Math at the Core: Middle School Collection.

• ## Scale City | Proportional Relationships in the Real World

In this video, students visit the Kentucky Horse Park where they are introduced to the question How are speed, time, and distance interrelated? The accompanying activity builds on a demonstration from the video of the length of Man o’ War’s stride versus the length of a person’s stride by allowing students to measure their own strides versus that of the great racehorse. This resource is part of the Math at the Core: Middle School Collection.

• ## Scale City | Proportions and Music in the Real World

In this video—through footage of the calliope aboard the Belle of Louisville, a church pipe organ, and various instruments at a recording studio—students are introduced to the mathematical concept that the length of a musical pipe or a string has a proportional relationship with the sound it produces.  In the accompanying activity, stringed instruments are used to demonstrate the concept presented in the video. This resource is part of the Math at the Core: Middle School Collection.

• ## Determining Surface Area with Unit Blocks

Use your spatial reasoning skills to calculate the surface area when given a 3D figure. This video focuses on a right rectangular prism and shows you how unit blocks can help you visualize, then calculate the surface area. This video was submitted through the Innovation Math Challenge, a contest open to professional and nonprofessional producers. This resource is part of the Math at the Core: Middle School collection.

• ## Areas of Irregular Shapes: Building Sailboats

Learn how wooden boat builders use a variety of mathematical concepts when custom designing their vessels. This video focuses on how area, volume, and measurements of irregular shapes are used in the engineering process, taking math out of the classroom and into real world problem solving.
• ## Scale City | Reviewing Ratios, Proportions, and Scale

In this interactive, students put quarters into a virtual vending machine and solve 16 problems involving ratios and proportions in order to receive “treats.” In the accompanying classroom activity, small groups of students take turns solving the problems to see which group is quickest to finish the game. This resource is part of the Math at the Core: Middle School Collection.

• ## Commutative and Associative Properties of Addition

Generate equivalent expressions using two additive properties. This video focuses on using the associative and commutative properties of addition to combine like terms, simplify expressions, and create equivalent expressions.

This video was submitted through the Innovation Math Challenge, a contest open to professional and nonprofessional producers and is part of the Math at the Core: Middle School collection.

• ## Soul Food Junkies: Survey

Consider the relationships between health and diet and reflect on your own food choices with this video from the Center for Asian American Media. This resource is part of the Math at the Core: Middle School Collection.

• ## Addition of Positive and Negative Integers

Introducing a card game that your students can play in small groups to develop their addition skills. This video focuses on addition of positive and negative numbers and briefly touches on subtraction of integers.

This video was submitted through the Innovation Math Challenge, a contest open to professional and nonprofessional producers and is part of the Math at the Core: Middle School collection.

• ## One-Variable Equations: How Much Did He Read?

Visualize a word problem in multiple ways to develop your problem solving skills. This video focuses on converting a problem with fractions into a one-variable equation and alternately modeling it using unit blocks.

This video was submitted through the Innovation Math Challenge, a contest open to professional and nonprofessional producers and is part of the Math at the Core: Middle School collection.

• ## Comparative Experimental Design

Test your memory on three letter words and non-words. This interactive exercise focuses on the designs of comparative experimental studies versus comparative observational studies. This resource is part of the Math at the Core: Middle School Collection.

• ## The Lowdown | Measuring Variability Through Tracking Wildfires

In this interactive, learn about wildfires in the western US using an interactive map profiling active fires and graphs depicting historical data. In the accompanying classroom activity, students review aggregated data for 11 western states and then focus on data from a single state, describing the shape of the data and comparing changes across decades. To get the most out of this activity, students should be comfortable calculating mean and be familiar with percent. This resource is part of the Math at the Core: Middle School Collection.

• ## Logical Leaps | Fractions, Mixed Numbers, and Decimals on the Number Line

In this interactive, students use logic to solve three riddles involving a frog jumping contest and then place the contestants’ jumps at the correct points on the number line. Numbers are randomized so that the frogs’ placements on the number line are different each time one of the three riddles appears. The accompanying classroom activity provides a review of equivalent values of fractions and decimals and a response sheet to help students work with the interactive. This resource is part of the Math at the Core: Middle School Collection.

• ## Summarize Numerical Data Sets Using Venn Diagrams

In this Cyberchase media gallery, explore Venn diagrams and how they are used to represent data overlap and differences. Comical and real-world examples are provided using two and three circles, plus a circle-within-a-circle representation. In the accompanying classroom activity, students sort classmates according to given characteristics, such as the color or design of their clothing or footwear. They then complete a Venn diagram that demonstrates the sorting rule. This resource is part of the Math at the Core: Middle School Collection.

• ## Data Analysis Using Mean, Median, Mode, and Range

In this media gallery, a series of videos examines the mathematical concepts of mean, median, mode, and range. The accompanying classroom activity asks students to build on what they’ve learned by playing a game called "Sure Shots." In this game, students are directed to find out how many attempts it takes, on average, to get a pom-pom into a can. Students make a series of attempts and collect the data. Then, after a group discussion, they take the data and determine the mean, median, mode, or range. This resource is part of the Math at the Core: Middle School Collection.

• ## Recognize and Represent Proportional Relationships Between Quantities: Ratio, Proportion, Cross Multiply, and Divide

In this Cyberchase media gallery, learn about ratio and proportion and how to use an algebraic shortcut to solve proportion problems. In the accompanying classroom activity, students play a game called the "Pom-Pom Nose Push," in which they collect data and determine the ratio of time to distance. This resource is part of the Math at the Core: Middle School Collection.

• ## The Lowdown | Prison Population: Real World Statistical Variability

This infographic represents the dramatic change in the federal and state prison population from 1925 to the present. While the United States makes up about 5% of the world’s population, it houses roughly 25% of the world’s prisoners. In the accompanying classroom activity, students make sense of these data by recording and discussing their observations, finding patterns, and calculating median and range. This resource is part of the Math at the Core: Middle School Collection.

• ## Scale City | Inverse Proportions and Shadows in the Real World

In this video, students take a quick trip through the history of drive-in theaters and are then asked to consider the question, "What is the relationship between the size of an object’s shadow and the object’s distance from a light source?" In the accompanying classroom activity, students do a hands-on experiment about the size of their own shadows at different distances from a projector or other light source. This resource is part of the Math at the Core: Middle School Collection.

• ## Scale City | Inverse Proportions and Shadows in Practice

In this interactive, students explore what happens to a figure’s shadow on a movie screen as the figure moves away from the projector. They also use approximate measurements to complete a chart of distance from light source versus height of shadow on the screen. As the chart is completed, students see how the relationships are represented graphically. The accompanying activity provides discussion questions for students to consider as they work through the interactive, as well as a chart for them to complete as they measure and compute values based on the interactive. This resource is part of the Math at the Core: Middle School Collection.