Videos:

1. Adding and Subtracting Polynomials 
2. Simply a polynomial
3. Adding Polynomials
4. Opposite of a Polynomial
5. Subtracting Polynomials
6. Adding and Subtracting Polynomials 1
7. Adding and Subtracting Polynomials 2
8. Adding and Subtracting Polynomials 3

Cameron's Adding and subtracting polynomials help page

Help videos here

Games here

practice problems here

Example problems here