This is episode 7, from Mathtrain.com.  "Bob" shows us "Prime Factorization" (factor trees).
 
Mathcasts, mostly student-created and hosted.

Mathtrain.TV: Episode 7

Student-Created Tutorials Companion to our iTunes Education Podcast

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Find the volume inside the cylinder, but outside the sphere.

Part of the student-created tutorial project at Mathtrain.TV.Mathtrain.TV is a free, educational "kids teaching kids" project from Mr. Marcos and his Students at Lincoln Middle School in Santa Monica, CA. StudentCreated.TV is a free site for sharing student-created tutorials for all school subjects. Both sites are mobile-enabled.

Mathtrain.TV:Ep.129, Sphere and Cylinder Volume

A mini-review of multiplying exponents.

Part of the student-created tutorial project at Mathtrain.TV.Mathtrain.TV is a free, educational "kids teaching kids" project from Mr. Marcos and his Students at Lincoln Middle School in Santa Monica, CA. StudentCreated.TV is a free site for sharing student-created tutorials for all school subjects. Both sites are mobile-enabled.

Mathtrain.TV:Ep.128, Mini Exponent Review

Let's take a visual look at the area of a circle.

Part of the student-created tutorial project at Mathtrain.TV.Mathtrain.TV is a free, educational "kids teaching kids" project from Mr. Marcos and his Students at Lincoln Middle School in Santa Monica, CA. StudentCreated.TV is a free site for sharing student-created tutorials for all school subjects. Both sites are mobile-enabled.

Mathtrain.TV:Ep.127, Visual Look at Area of a Circle

Shane, a 7th grader, show us the vertical line test for functions.  She created this tutorial on her iPad, using the free ScreenChomp app.

It's our 7th Anniversary month!  Yay!

Part of the student-created tutorial project at Mathtrain.TV.Mathtrain.TV is a free, educational "kids teaching kids" project from Mr. Marcos and his Students at Lincoln Middle School in Santa Monica, CA.StudentCreated.TV is a free site for sharing student-created tutorials for all school subjects. Both sites are mobile-enabled.

Mathtrain.TV:Ep.126, Vertical Line Test for Functions

Middle school student Shane shows us a Simple Interest problem.  She created this tutorial using the free ScreenChomp app on her iPad and Camtasia Studio was later used for adding the pop ups.

 Part of the student-created tutorial project at Mathtrain.TV.Mathtrain.TV is a free, educational "kids teaching kids" project from Mr. Marcos and his Students at Lincoln Middle School in Santa Monica, CA.

Mathtrain.TV plays on mobile devices, including iPads & iPhones.
StudentCreated.TV is a free site for sharing student-created tutorials for all school subjects. Also mobile-enabled.

Mathtrain.TV: Episode 7

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