It covers the following subjects:

- Arithmetic series
- Complementary and supplementary angles
- Vertical angles
- Isoceles, scalene, and equilateral triangles
- Acute, obtuse, and right angles
- Triangle angle sum theorem
- Solving word problems
- Order of operations

This video covers the following topics:

**Triangle angle sum theorem**: The sum of a triangle’s angles equals 180 degrees.

**Triangle inequality theorem**: In any triangle, the sum of any two sides must be greater than the other side.

Video #202

This video covers the definitions of the following terms:

- Polygon
- Triangle
- Equilateral triangle
- Isosceles triangle
- Scalene Triangle
- Acute Triangle
- Right Triangle
- Obtuse Triangle

Video #202

Part A:

Part B:

This video covers the following definitions:

- right angle
- acute angle
- obtuse angle
- straight angles
- adjacent angles
- complementary angles
- supplementary angles
- vertical angles

This is MathDoctor.net Video #201.

Common Core covers a lot of material. And because of the constraints of the curriculum, teachers are often forced to cover it fast, and they are often forced to cover it in ways that are lacking in clarity.

As I worked with my own son, I discovered one important secret: Most of the material is **very** elementary, and students shouldn’t have any trouble understanding it, if it’s presented in a clear manner. But the layout of the curriculum does not encourage clarity. I found that I needed to present the material to my son in a **clear and understandable** way. And as soon as I presented the material clearly, both my son and I realized how simple it really was.

Since my explanations helped my own son, I assume that other parents and students can benefit as well. Therefore, I will be posting this series of videos, and over the course of the year, I will have explained the entire sixth grade Common Core curriculum.

In my introductory video for parents, I explain more: