1. Home
  2. Grade 7-12 Math Lesson Library
Grades 7 to 12

Grade 7-12 Math Lesson Library

The maths of Grades 7 to 12: the DepEd MATATAG curriculum year by year for Grades 7 to 10 — number and algebra, measurement and geometry, and data and probability — then General Mathematics, Precalculus, Solid Mensuration and Statistics and Probability for Senior High. Every lesson is a short slide deck ending in a 5-question check.

Free

Grade 7 · Quarter 1

Sets, Subsets, and Venn Diagrams

Roster and rule form, subsets and how many a set has, union, intersection, complement and difference, and Venn diagrams for two-group survey problems.

Read the lesson »
Free

Grade 7 · Quarter 1

The Real Number System

Classify a number into every subset of the real numbers it belongs to, name the commutative, associative, distributive, identity and inverse properties, and use them to compute mentally.

Read the lesson »
Free

Grade 7 · Quarter 1

Absolute Value and Operations on Integers

Absolute value as distance from zero, adding and subtracting integers including subtracting a negative, the sign rules for multiplying and dividing, and order of operations with negatives.

Read the lesson »
Free

Grade 7 · Quarter 1

Operations on Fractions and Decimals

Add, subtract, multiply and divide fractions and mixed numbers, convert between fractions and decimals, and handle word problems that mix the two.

Read the lesson »
Free

Grade 7 · Quarter 1

Square Roots and Estimating Irrational Numbers

Exact square roots of perfect squares, telling a rational root from an irrational one, estimating a root between two integers and to the nearest tenth, and placing it on a number line.

Read the lesson »
Free

Grade 7 · Quarter 1

Cube Roots of Perfect Cubes

Perfect cubes and their cube roots, how a cube root differs from a square root, and why a cube root of a negative number exists when a square root does not.

Read the lesson »
Free

Grade 7 · Quarter 1

Scientific Notation

Write large and small numbers as a x 10 to the n, convert back to standard form, compare numbers in scientific notation, and multiply and divide them.

Read the lesson »

Free

Grade 8 · Quarter 1

Operations on Polynomials

Classify polynomials by terms and degree, add and subtract by combining like terms, multiply with FOIL, and divide a polynomial by a monomial.

Read the lesson »
Free

Grade 8 · Quarter 1

Special Products

The square of a binomial, the sum and difference pattern giving a difference of squares, products with a common term, the square of a trinomial and the cube of a binomial.

Read the lesson »
Free

Grade 8 · Quarter 1

Factoring by Greatest Common Factor and Grouping

Find the greatest common factor of monomials, factor it out, factor four-term polynomials by grouping, and take out a common binomial factor.

Read the lesson »
Free

Grade 8 · Quarter 1

Factoring Differences of Squares and Cubes

Factor a difference of two squares, a sum of cubes and a difference of cubes, take the GCF out first to factor completely, and use the squares pattern for mental arithmetic.

Read the lesson »
Free

Grade 8 · Quarter 1

Factoring Trinomials

Factor trinomials with leading coefficient 1 by finding two numbers, use the AC method when the leading coefficient is not 1, and recognise perfect square trinomials.

Read the lesson »
Free

Grade 8 · Quarter 1

Simplifying Rational Algebraic Expressions

What makes an expression rational, finding the excluded values, factoring top and bottom completely, and simplifying to lowest terms by cancelling common factors.

Read the lesson »
Free

Grade 8 · Quarter 1

Operations on Rational Algebraic Expressions

Multiply and divide rational expressions by factoring and cancelling, add and subtract with like and unlike denominators using the LCD, and state the restrictions afterwards.

Read the lesson »
Free

Grade 8 · Quarter 1

Rational Algebraic Equations

Solve equations with a variable in the denominator by clearing the LCD, and check every answer against the restrictions so an extraneous root never slips through.

Read the lesson »

Free

Grade 8 · Quarter 2

Sequences and Their Rules

Find the rule behind a sequence, write the nth term of an arithmetic sequence, and tell arithmetic from geometric and from sequences that are neither.

Read the lesson »
Free

Grade 8 · Quarter 2

Linear Inequalities in One Variable

Solve linear inequalities in one variable, remember that multiplying or dividing by a negative reverses the sign, and show the solution on a number line.

Read the lesson »
Free

Grade 8 · Quarter 2

The Coordinate Plane and Graphing Lines

Plot points and name quadrants on the Cartesian plane, find intercepts, and graph a linear equation from a table of values or from its intercepts.

Read the lesson »
Free

Grade 8 · Quarter 2

Distance and the Midpoint of a Line Segment

The distance formula as the Pythagorean theorem on the coordinate plane, the midpoint as the average of the coordinates, and working backwards to a missing endpoint.

Read the lesson »
Free

Grade 8 · Quarter 2

Slope and Forms of Linear Equations

Compute slope from two points, write a line in slope-intercept and point-slope form, convert to standard form, and read slope as a constant rate of change.

Read the lesson »
Free

Grade 8 · Quarter 2

Solving Systems of Linear Equations

Solve systems of linear equations by substitution and by elimination, and recognise when a system has no solution or infinitely many.

Read the lesson »
Free

Grade 8 · Quarter 2

Word Problems with Systems

Turn two-unknown word problems into systems — number, money, mixture, age and cost problems — then solve and check both conditions.

Read the lesson »
Free

Grade 8 · Quarter 2

Linear Inequalities in Two Variables

Graph a linear inequality in two variables — solid or broken boundary line, which side to shade, and how to test a point to be sure.

Read the lesson »

Free

Grade 9 · Quarter 3

Basic Geometric Concepts and Notation

Points, lines and planes, the notation for segments, rays and angles, betweenness and the segment addition postulate, and classifying angles.

Read the lesson »
Free

Grade 9 · Quarter 3

Parallel Lines Cut by a Transversal

The eight angles formed when a transversal cuts two parallel lines — corresponding, alternate interior, alternate exterior and co-interior — and how to prove lines parallel.

Read the lesson »
Free

Grade 9 · Quarter 3

Parallelograms and Special Quadrilaterals

Properties of parallelograms and of rectangles, rhombi and squares, the tests that prove a quadrilateral is a parallelogram, and how the family tree fits together.

Read the lesson »
Free

Grade 9 · Quarter 3

Trapezoids, Kites, and the Midline Theorem

Trapezoids and isosceles trapezoids, the median or midsegment, kites and their perpendicular diagonals, and the midline theorem for triangles.

Read the lesson »
Free

Grade 9 · Quarter 3

If-Then Statements and Reasoning

Conditional statements, their converse, inverse and contrapositive, why only the contrapositive is always equivalent, and inductive versus deductive reasoning.

Read the lesson »
Free

Grade 9 · Quarter 3

Triangle Congruence

Corresponding parts from a congruence statement, the SSS, SAS, ASA, AAS and HL tests, why SSA and AAA fail, and using CPCTC.

Read the lesson »
Free

Grade 9 · Quarter 3

Triangle Congruence Proofs

Write a two-column proof of triangle congruence — the given, the reasons you may cite, the free facts like reflexive sides and vertical angles, and finishing with CPCTC.

Read the lesson »
Free

Grade 9 · Quarter 3

Similar Triangles and Proportionality

Similarity as same shape with proportional sides, the AA, SSS and SAS similarity tests, finding a missing side with a proportion, and how area scales with the square of the ratio.

Read the lesson »
Free

Grade 9 · Quarter 3

Triangle Theorems

The isosceles triangle theorem and its converse, the angle bisector and perpendicular bisector theorems, and the four centres a triangle has.

Read the lesson »

Free

Grade 11-12 · Gen Math: Functions

Functions, Function Notation, and Evaluating Functions

What makes a relation a function, reading and using function notation, evaluating a function at a number or an expression, and writing a piecewise function for a fare that changes partway.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Operations on Functions and Composition

Adding, subtracting, multiplying and dividing functions, the domain the quotient loses, and composition — why f of g means g goes first and why the order almost never commutes.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Transformations of Functions

Shift, reflect, stretch and shrink the graph of any function: which change moves it up, which moves it sideways against the sign, which flips it, and how to track points and the domain and range through all of them at once.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Rational Functions, Equations, and Inequalities

Rational functions and their restrictions, solving a rational equation by clearing the denominators, why every answer must be checked for extraneous roots, and why an inequality needs a sign chart instead.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Intercepts, Zeroes, and Asymptotes of Rational Functions

Reading a rational function's graph from its algebra — zeroes from the top, vertical asymptotes from the bottom, the horizontal asymptote from the degrees, and the hole that appears when a factor cancels.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

One-to-One Functions and Their Inverses

One-to-one functions and the horizontal line test, finding an inverse by swapping x and y, why the domain and range trade places, and checking an inverse by composing the two functions.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Exponential Functions, Equations, and Inequalities

What makes a function exponential, solving exponential equations by matching bases, rewriting numbers to a common base, and the sign flip that a base below 1 forces on an inequality.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Graphing Exponential Functions

The shape every exponential graph shares, the point (0, 1) they all pass through, growth against decay, the horizontal asymptote, and what shifting and reflecting do to all three.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Logarithms and the Laws of Logarithms

A logarithm is an exponent — converting between log and exponential form, the product, quotient and power laws, common and natural logs, and the change-of-base formula.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Logarithmic Equations and Inequalities

Solving logarithmic equations by rewriting in exponential form or by equating arguments, combining several logs into one first, and why every answer must be tested against the domain.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Graphing Logarithmic Functions

The logarithmic graph as the exponential reflected in y = x, the point (1, 0) they all share, the vertical asymptote, and how a shift inside the bracket moves both the asymptote and the domain.

Read the lesson »
Free

Grade 11-12 · Gen Math: Functions

Growth, Decay, and Half-Life

Exponential growth and decay models, doubling time and half-life, reading the model straight from the wording, and using logarithms to solve for the time when the exponent is unknown.

Read the lesson »

Free

Grade 11-12 · Gen Math: Business Math

Simple Interest

Simple interest as a flat charge on the original principal, the formula I = Prt, matching the units of rate and time, and finding any one of the four quantities from the other three.

Read the lesson »
Free

Grade 11-12 · Gen Math: Business Math

Compound Interest

Compound interest as interest earning interest, the formula A = P(1 + r)ⁿ, how it pulls away from simple interest over time, and finding the principal or the rate from the amount.

Read the lesson »
Free

Grade 11-12 · Gen Math: Business Math

Compounding More Than Once a Year

Compounding more than once a year — dividing the nominal rate by the number of periods, multiplying the years by it, and why more frequent compounding pays a little more.

Read the lesson »
Free

Grade 11-12 · Gen Math: Business Math

Simple Annuities

Annuities as a stream of equal payments at equal intervals, the future and present value formulas, the difference between an ordinary annuity and an annuity due, and finding the payment from a target.

Read the lesson »
Free

Grade 11-12 · Gen Math: Business Math

General and Deferred Annuities

General annuities, where the payment interval and the compounding period differ, converting to an equivalent rate so the simple-annuity formula applies, and deferred annuities whose payments start later.

Read the lesson »
Free

Grade 11-12 · Gen Math: Business Math

Stocks and Dividends

Shares, par value and market value, working out a dividend from the par value rather than the price paid, the dividend yield, and the gain or loss made on selling.

Read the lesson »
Free

Grade 11-12 · Gen Math: Business Math

Bonds

Bonds as a loan to the issuer — face value, coupon rate and maturity, working out a coupon payment, why a bond trades above or below face value, and the current yield.

Read the lesson »
Free

Grade 11-12 · Gen Math: Business Math

Business and Consumer Loans

Consumer and business loans, seeing a loan as the present value of an annuity, the amortisation formula for the regular payment, what an amortisation schedule shows, and the true cost of borrowing.

Read the lesson »

Free

Grade 11-12 · Precalculus: Analytic Geometry

The Circle

The circle as a conic section, its standard and general forms, completing the square in both variables to recover the centre and radius, and the two degenerate cases a general equation can hide.

Read the lesson »
Free

Grade 11-12 · Precalculus: Analytic Geometry

The Parabola

The parabola as the set of points equidistant from a focus and a directrix, the four standard forms, finding the vertex, focus, directrix and latus rectum, and why the reflector property matters.

Read the lesson »
Free

Grade 11-12 · Precalculus: Analytic Geometry

The Ellipse

The ellipse as the set of points whose distances to two foci add to a constant, the relationship a² = b² + c², reading the major axis from the larger denominator, and eccentricity.

Read the lesson »
Free

Grade 11-12 · Precalculus: Analytic Geometry

The Hyperbola

The hyperbola as the set of points whose distances to two foci differ by a constant, why the positive term decides the opening direction, c² = a² + b², and the asymptotes that guide the branches.

Read the lesson »
Free

Grade 11-12 · Precalculus: Analytic Geometry

Recognising a Conic from Its Equation

Telling the four conics apart from a general second-degree equation by looking at the squared terms, their signs and their coefficients, and the degenerate cases that hide inside each one.

Read the lesson »
Free

Grade 11-12 · Precalculus: Analytic Geometry

Situational Problems Involving Conics

Setting up a coordinate system for a real conic — parabolic dishes and bridge cables, elliptical arches and whispering galleries — then reading the answer back out in the units of the problem.

Read the lesson »
Free

Grade 11-12 · Precalculus: Analytic Geometry

Systems of Non-Linear Equations

Solving systems where at least one equation is not linear — substitution, elimination between two conics, checking every candidate, and reading the number of solutions off the picture.

Read the lesson »

Free

Grade 11-12 · Precalculus: Trigonometry

Angles in Standard Position and Radian Measure

Angles in standard position, converting between degrees and radians, coterminal and reference angles, and arc length and sector area, which only work in radians.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

The Unit Circle and the Circular Functions

The unit circle as the definition of sine and cosine for any angle, the coordinates of the special angles, the signs in each quadrant, and using reference angles to find any value.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Graphs of the Circular Functions

The graphs of sine, cosine and tangent — where they come from on the unit circle, their period, range and key points, and why tangent has asymptotes where the others do not.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Amplitude, Period, and Phase Shift

Reading amplitude, period, phase shift and vertical shift from y = a sin(b(x − c)) + d, why the period is 2π over b, and why the phase shift needs b factored out first.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Fundamental Trigonometric Identities

The reciprocal, quotient and Pythagorean identities, the even-odd identities, and the method for proving an identity — work on one side only until it matches the other.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Sum and Difference Identities

The sum and difference formulas for sine, cosine and tangent, the sign flip that catches everyone in the cosine version, and using them to find exact values for angles like 15 and 75 degrees.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Double-Angle and Half-Angle Identities

Double-angle formulas for sine, cosine and tangent, the three equivalent forms of cos 2A and when each is useful, and the half-angle formulas whose sign comes from the quadrant.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Inverse Trigonometric Functions

Why sine, cosine and tangent need restricted domains before they can be inverted, the principal value ranges of arcsin, arccos and arctan, and evaluating compositions of a function with its inverse.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Trigonometric Equations

Solving trigonometric equations — finding every solution in an interval rather than one, factoring and using identities to reduce to a single function, and why dividing by a trig factor loses roots.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

The Polar Coordinate System

Locating a point by distance and direction instead of across and up, converting both ways between polar and rectangular coordinates, and why a polar point has infinitely many names.

Read the lesson »
Free

Grade 11-12 · Precalculus: Trigonometry

Situational Problems Involving Trigonometry

Trigonometry in real situations — bearings, angles of elevation and depression, choosing between the sine and cosine laws, and simple harmonic motion modelled by a sine function.

Read the lesson »

Free

Grade 11-12 · Solid Mensuration

Naming Solids, Nets, and Cross-Sections

Naming a solid by its base, unfolding it into a net, slicing it into a cross-section, and the face-vertex-edge count that checks your work.

Read the lesson »
Free

Grade 11-12 · Solid Mensuration

Surface Area and Volume of a Prism

Volume as base area times height for any prism, lateral area as perimeter times height, and the unit conversions that turn cubic centimetres into litres.

Read the lesson »
Free

Grade 11-12 · Solid Mensuration

Surface Area and Volume of a Pyramid

Why a pyramid is one third of the prism on the same base, the right triangle that turns height into slant height, and the lateral area formula that needs the slant.

Read the lesson »
Free

Grade 11-12 · Solid Mensuration

Surface Area and Volume of a Cylinder and a Cone

A cylinder as a prism with a circular base and a cone as a pyramid with one, the rolled-out rectangle that gives lateral area, and where the cone's slant height comes from.

Read the lesson »
Free

Grade 11-12 · Solid Mensuration

Surface Area and Volume of a Sphere

The two sphere formulas and how to keep them apart, the flat face a hemisphere still has, and building a composite solid out of pieces you already know.

Read the lesson »
Free

Grade 11-12 · Solid Mensuration

Trigonometry Inside a Solid

Finding the right triangle hidden inside a pyramid, a cone or a box, telling the slant height from the lateral edge, and the angles a face and a diagonal make with the base.

Read the lesson »

Free

Grade 11-12 · Statistics and Probability

Random Variables, Discrete and Continuous

Turning an outcome into a number, telling a discrete random variable from a continuous one, and listing the values a random variable can take before any probability is worked out.

Read the lesson »
Free

Grade 11-12 · Statistics and Probability

Discrete Probability Distributions

Building a probability distribution from the outcomes, the two conditions every valid distribution must meet, and reading probabilities off a histogram.

Read the lesson »
Free

Grade 11-12 · Statistics and Probability

Mean, Variance, and Standard Deviation of a Random Variable

The expected value as a weighted average, the shortcut formula for variance, and why the mean of a random variable need not be a value the variable can take.

Read the lesson »
Free

Grade 11-12 · Statistics and Probability

The Normal Distribution and z-Scores

The bell curve and what makes it normal, converting a raw score to a z-score, reading areas from the z-table, and the empirical 68-95-99.7 rule.

Read the lesson »
Free

Grade 11-12 · Statistics and Probability

Sampling Distributions and the Central Limit Theorem

Why a sample mean varies, the standard error and why dividing by root n shrinks it, and the Central Limit Theorem that makes the sample mean normal whatever the population looks like.

Read the lesson »
Free

Grade 11-12 · Statistics and Probability

Point Estimates and Confidence Intervals

A point estimate and why it is never enough on its own, building a confidence interval from the sample mean and the margin of error, and what 95 percent confidence actually claims.

Read the lesson »
Free

Grade 11-12 · Statistics and Probability

Testing a Hypothesis About a Mean

Writing the null and alternative hypotheses, computing the test statistic, comparing it against a critical value, and what a rejected or retained null actually lets you say.

Read the lesson »
Free

Grade 11-12 · Statistics and Probability

Correlation and the Least-Squares Regression Line

Reading a scatter plot, what the correlation coefficient r does and does not say, fitting the least-squares line, and using it to predict without going past the data.

Read the lesson »

Stuck on one of these?

Send us a message on Facebook and we will go through it together, step by step.