Audio
Science Friday Initiative

Science Friday: The Incredible Shrinking Proton?

9th - 10th
New measurements from a group of physicists indicate that the proton may be about 4 percent smaller than previously thought. But what does that mean?
Instructional Video
Sophia Learning

Sophia: Atomic Number: Lesson 2

9th - 10th
This lesson explains what is represented by the atomic number, and how it varies from one element to the next. It is 2 of 7 in the series titled "Atomic Number."
Instructional Video
Other

You Tube: Where Does the Sun Get Its Energy?

9th - 10th
The sun has been producing light for about five billion years but where does all its energy come from? The most common idea is that the sun is burning gas - like a giant fireball in the sky. If this were true, the sun would have gone out...