This Week's Work : Week 17 - for Inquisitive Young Mathletes

Part I work : Algebra : Quadratic Equations from AoPS Videos

Introductory level :

Factoring Quadratics part 1

Factoring Quadratics part 2

Online worksheets to practice basic skills from kutasoftware

Factoring Quadratic Polynomials : both easy and hard
(instant feedback is on the same pdf file)

Good stuff (for competition math)

Vieta for Quadratics Part 1

Vieta for Quadratics Part II

Tackling Problems with Vieta