Free math videos on BrainPOP (no trial or subscription needed to watch):

And just to give you an idea of how vast the BrainPOP video library is, here is a list of all titles available to watch with a free trial or subscription (as of March 2008). Or, check out some the math titles below:

*BrainPOP*: Absolute Value, Adding and Subtracting Fractions, Adding and Subtracting Fractions Advanced, Adding and Subtracting Integers, Adding and Subtracting Integers Advanced, Area of Polygons, Associative Property, Basic Probability, Binary, Calculus, Commutative Property, Comparing Prices, Converting Fractions to Decimals, Coordinate Plane, Decimals, Distance, Rate, and Time, Distributive Property, Division, Equations with Variables, Estimating Distance, Exponents, Fibonacci Sequence, Game Theory, Geometry, Graphing Linear Equations, Graphing or Solving Inequalities, Graphs, Greatest Common Factor, Inequalities, Interest, Isaac Newton, Mean, Median, Mode, and Range, MeasuringAngles, Measuring Circles, Metric vs. Imperial, Mixed Numbers, Monomials, Multiplication, Multiplying and Dividing fractions, Negative Exponents, Order of Operations, Parallel and Perpendicular Lines, Percents, Pi, Polygons, Polyhedrons, Polynomials, Prime Factorization, Probability of Compound Events, Probability of Independent Events, Problem Solving using Tables, Proportions, Pythagorean Theorem, Rational and Irrational Numbers, Ratios, Roman Numerals, Rounding, Similar Triangles, Simple Equations, Slope and Intercept, Solving Equations, Square Roots, Standard and Scientific Notation, Supply and Demand, Taxes, Transformation, Two-Step Equations, Types of Triangles, Using a Calculator, Volume of Cylinders, Volume of Prisms, Word Problems

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BrainPOP Jr__: Arrays, Basic Adding, Basic Parts of a Whole, Basic Subtraction, Calendar & Dates, Dollars & Cents, Even & Odd, Inches & Feet, Parts of a Clock, Plane Shapes, Solid Shapes, Tally Charts & Bar Graphs, Time to the Hour