- Simplifying hairy fractions
- Simplifying rational expressions 2
- Simplifying rational expressions 3
- Simplifying rational expressions 4
- Simplifying rational expressions with exponent properties
- Simplifying resistor networks (article)
- Simplifying resistor networks (video)
- Simplifying square roots
- Simplifying square roots 2
- Sine and cosine come from circles
- Sine and cosine from rotating vector
- Sine of time
- Single-step simplification of radical expressions
- Single-step simplification of rational exponent expressions
- Sketching exponentials
- Sketching exponentials - examples
- Skip-count by 10s
- Skip-count by 5s
- Skip-counting by 100s
- Slicing 3D figures
- Slope-intercept equation from a graph
- Slope-intercept equation from two solutions
- Slope and triangle similarity
- Slope fields
- Slope from a graph
- Slope from an equation in slope-intercept form
- Slope from an equation in standard form
- Slope from two solutions
- Slope intuition
- Slope of secant lines
- Sneak Peek
- Solid geometry
- Solutions to quadratic equations
- Solve any system of two linear equations
- Solve equations with one rational expression (advanced)
- Solve equations with one rational expression (basic)
- Solve equations with two rational expressions
- Solve exponential equations using logarithms (base-10 and base-e)
- Solve exponential equations using logarithms (base-2 and other bases)
- Solve exponential equations using properties of exponents (advanced)
- Solve exponential equations using properties of exponents (basic)
- Solve factorable quadratic equations (leading coefficient is other than 1)
- Solve linear equations with unknown coefficients
- Solve problems with bar graphs 1
- Solve problems with bar graphs 2
- Solve problems with line plots 1
- Solve problems with picture graphs 1
- Solve quadratic equations using the quadratic formula
- Solve square-root equations (advanced)
- Solve square-root equations (basic)
- Solve systems of linear equations with elimination (advanced)
- Solve systems of linear equations with elimination (basic)
- Solve systems of linear equations with substitution
- Solving basic multiplication and division equations
- Solving equations in terms of a variable
- Solving for the y-intercept
- Solving for unknown angles
- Solving matrix equations
- Solving problems with bar graphs 3
- Solving problems with picture graphs 2
- Solving problems with similar and congruent triangles
- Solving proportions
- Solving proportions 2
- Solving quadratics by completing the square 1
- Solving quadratics by completing the square 2
- Solving quadratics by factoring
- Solving quadratics by taking the square root
- Solving ratio problems with tables
- Solving rational equations 1
- Solving rational equations 2
- Solving similar triangles 1
- Solving similar triangles 2
- Solving systems of equations graphically
- Solving systems of linear equations with elimination 1
- Solving systems of linear equations with elimination 2
- Solving systems of linear equations with substitution
- Solving systems of two linear equations
- Sorting absolute value word problems
- Special Project
- Special derivatives
- Special derivatives quiz
- Special right triangles
- Spunky Sam
- Square and cube challenge
- Square roots of perfect squares
- Squeeze theorem
- Standard deviation of a population
- Starky
- Statistical questions
- Steadfastness
- Sticktoitiveness
- Streak
- Streak Leaderboard
- Structure in expressions 1
- Student story: College brings new friends, learning, and freedom
- Student story: College expands opportunities
- Student story: College increases confidence
- Student story: College offers exposure to diversity
- Student story: Extracurriculars that are a passion
- Student story: Extracurriculars that are leadership opportunities
- Student story: Extracurriculars that are nontraditional
- Student story: Extracurriculars that are self created
- Student story: Extracurriculars that carry over from high school to college
- Student story: High school classes
- Student story: Overcoming anxiety around not fitting in as an obstacle to college
- Student story: Overcoming cultural obstacles to college
- Student story: Overcoming family obstacles to college
- Student story: Overcoming financial obstacles to college
- Student story: Overcoming immigration obstacles to college
- Student story: Overcoming lack of high school support as an obstacle to college
- Student story: Overcoming social obstacles to college
- Student story: Overcoming the financial aid process as an obstacle to college
- Student story: Overcoming time management obstacles to college
- Student story: Prioritizing financial aid, major, and location in the college search
- Student story: Prioritizing financial aid in the college search
- Student story: Prioritizing location in the college search
- Student story: Prioritizing size, campus, major, and selectivity in the college search
- Student story: Prioritizing size, selectivity, diversity, and financial aid in the college search
- Student story: Standardized tests
- Student story: Work study as a study hall
- Sub-light Speed
- Subtract 1-digit numbers with regrouping
- Subtract 10s and 100s (no regrouping)
- Subtract 1 or 10
- Subtract 2- and 3-digit numbers (no regrouping)
- Subtract 2-digit numbers (no regrouping)
- Subtract tens
- Subtract within 10
- Subtract within 100
- Subtract within 1000: Level 1
- Subtract within 1000: Level 2
- Subtract within 100: Level 1
- Subtract within 20
- Subtract within 5
- Subtracting 1s or 10s (no regrouping)
- Subtracting decimals
- Subtracting decimals 0.5
- Subtracting decimals 2
- Subtracting decimals 2 (with the standard algorithm)
- Subtracting decimals 3 (with the standard algorithm)
- Subtracting decimals without the standard algorithm 1
- Subtracting decimals without the standard algorithm 2
- Subtracting decimals without the standard algorithm 3
- Subtracting decimals without the standard algorithm 4
- Subtracting decimals without the standard algorithm 5
- Subtracting decimals without the standard algorithm 6
- Subtracting decimals without the standard algorithm 7
- Subtracting fractions with common denominators
- Subtracting fractions with unlike denominators
- Subtracting negative numbers intro
- Subtraction within 1000
- Subtraction word problems within 10
- Summary: Transforming functions
- Summer Surge 2015
- Summer of Script (Intro to JS)
- Summer of Script (Natural Simulations)
- Summer of Scripting Student
- Summing op-amp
- Sums of consecutive integers
- Super Knowledge Games
- Super Nova Tutor
- Supercharge Your Growth
- Supercharge goals
- Supercharge growth
- Superposition
- Support Advocate
- Support the KhanCampaign
- Surface and volume density word problems
- Surface area
- Surface area using nets
- Symbolic differentiation
- Symmetry and periodicity of trigonometric functions
- Symmetry of two-dimensional shapes
- Systems of equations word problems
- Systems of linear equations word problems
- Systems of linear equations word problems: Level 2
- Systems of linear inequalities word problems
- Systems of nonlinear equations
- Systems with one, zero, or infinite solutions
- Tangent slope is limiting value of secant slope
- Tangents to polar curves
- Team Athena
- Team Beta: Challange Teammate
- Team Beta: Challenge Champion
- Teen numbers
- Teen numbers 2
- Teen numbers 3
- Tell time with a labeled clock
- Tell time without labels