Activity
Annenberg Foundation

Annenberg Learner: Mathematics Illuminated: Combinatorics Counts

For Students 9th - 10th
Video presentation on combinatorics, or the "mathematics of counting complicated configurations." Offers several examples of combinatorics as used in real world situations and professions. [28:26]
Unit Plan
Texas A&M University

Wtamu Virtual Math Lab: College Algebra: The Fundamental Counting Principle

For Students 9th - 10th
Contains a tutorial on the fundamental counting principle that includes many examples and sample problems.
Activity
Other

Lake Tahoe Com. College: Fundamental Counting Principle

For Students 9th - 10th
Explains the fundamental principle of counting, which is the beginning point for any study of counting techniques such as combinations and permutations.
Lesson Plan
University of Colorado

University of Colorado: Discrete Mathematics Project: Venn Diagram Activity

For Teachers 9th - 10th
A lesson plan on the use of Venn diagrams for problem-solving.