In this professional development video, teachers can focus on the topic of number sense and computation by creating equivalent fractions that represent one-half through the use of geoblocks. This video can be used in conjunction with the *To Half or Half Not* Lesson Plan.

In this professional development video, teachers focus on the topic of measurement by having students measure the diameter, circumference, and area of circles made by a bubble print. This video can be used in conjunction with the *Bubble Mania* lesson plan.

Explore an historical story of how statisticians built the case against DDT as the culprit behind plummeting peregrine falcon population numbers in this video from the Against All Odds series. Students will learn how to use inference for regression to calculate consequences to a population. This information allowed scientists to make a strong case for the impact of DDT use on peregrine falcons as a whole.

In this professional development video, teachers focus on teaching the topic of linear systems by having students use matrices to solve a complex linear programming problem. This video can be used in conjunction with the "Meadows or Malls?" lesson plan.

A 1st grade teacher reviews what the class has learned about measurement and tasks students to use a tool, like a marker or a teddy bear, to measure the distance between two objects at home.

Learn classroom strategies for teaching how to multiply fractions using manipulatives in this professional development video from *Making Math Matter*.

Learn how probability can help predict events such as the daily weather or the likelihood that an asteroid will collide with Earth in this 11-minute video from the Against All Odds series. Host Pardis Sabeti demonstrates how probability, the mathematics of chance behavior, can help inform meteorologists and scientists with their predictions.

See how quality control management improved processing and testing samples at a laboratory in this video from Against All Odds. Host Pardis Sabeti demonstrates how to use control charts, common cause variables, and control limits in real-world situations.

Learn classroom strategies for teaching how to add three numbers up to 20 in this professional development video from *Making Math Matter*.

Learn classroom strategies for teaching how to multiply a fraction by a fraction in this professional development video from *Making Math Matter*.