1. How do you find the volume of a sphere?

3. Cylinder
Volume = Base x height
V = πr2h

4. Cylinder: V = πr2h
= πr2 x 2r
= 2πr3
Sphere: V = ???

6. Volume of hemisphere = 1 3 Volume of Cylinder
V = 1 3 (2πr3) or V= 2 3 πr3

7. Volume of
Hemisphere:
V= 2 3 πr3

8. V = 4 3 πr3
V = 4 3 π(3cm)3
V = 36πcm3

9. V = 4πr2
= 16π cm2
V = 4 3 πr3
V = πcm3
Students often get the formula for volume of a sphere confused with that of surface area of a sphere. Don’t do that.

11. V = 4 3 πr3 V = 4 3 π(5cm)3 V = 500 3 πcm3 LearnZillion Notes:
Remind students that they already know the volume of a cylinder is V=Bh or V= πr2h
Depict a sphere and a cylinder next to each other where each has equal radius and the cylinder has height=2r. Say: “We know that the volume of the cylinder will be V= πr2h = πr2(2r) = 2πr3. But what will the volume of the sphere be?”
Demonstrate (with images) that if you cut the sphere in half, the result is two hemispheres each with half the volume of the original sphere.
Demonstrate, with images, that it would take 3 hemispheres to fill the volume of the cylinder. This means the volume of the hemisphere is (1/3) the volume of the cylinder, or (1/3)( 2πr3) = (2/3)πr3
Explain that the volume of the sphere is twice that of the hemisphere: V= 2*[(2/3)πr3]= (4/3)πr3
Complete the hook example with sphere with radius 3cm

12. V = 4 3 πr3 V = 4 3 π(3cm)3 V = 36π cm3 LearnZillion Notes:
--The “Guided Practice” should include 1 practice problem that targets the skill that was used in the Core Lesson. Use the same vocabulary and process you used in the original lesson to solve this problem. You’ll be making a video in which you solve this question using your tablet and pen, so all you need to do is write the question on this slide.

13. LearnZillion Notes:

14. LearnZillion Notes:

15. LearnZillion Notes:
--”Quick Quiz” is an easy way to check for student understanding at the end of a lesson. On this slide, you’ll simply display 2 problems that are similar to the previous examples. That’s it! You won’t be recording a video of this slide and when teachers download the slides, they’ll direct their students through the example on their own so you don’t need to show an answer to the question.