Study tips
Quick mnemonics, worked examples and the mistakes to avoid. Each tip links to the full free study guide for the class.
English 9Comma Splices and FANBOYS: When to Use a CommaFix comma splices with FANBOYS, a semicolon or a period, and know when a comma is not needed, with two worked examples.Algebra IIExponent Rules: Product, Quotient, Power and ZeroLearn the exponent rules for multiplying, dividing and raising powers, plus the zero exponent, with worked examples and a common mistake.PhysicsKinematics Equations: Which One Do I Use?Pick the right kinematics equation by listing what you know, then solve two worked examples for velocity and distance.PrecalculusLaw of Sines vs Law of Cosines: Which One to Use and ExamplesKnow when to use the Law of Sines or the Law of Cosines for any triangle, with both formulas and two worked examples.ChemistryLimiting Reagent: How to Find It and Calculate Theoretical YieldFind the limiting reagent in four steps, then calculate the theoretical yield, with a worked example.AP BiologyMitosis vs Meiosis: PMAT, Key Differences and ExamplesMitosis or meiosis? Learn PMAT, count the divisions and daughter cells, and sort two examples, plus the mistake that costs points.ChemistryMole Conversions: Grams, Moles and Particles Step by StepConvert between grams, moles and particles using molar mass and Avogadro's number, with two worked examples and a common unit mistake.PhysicsNewton's Three Laws and F = ma: Rules and Worked ExamplesNewton's three laws in plain language, how to use F = ma, and two worked examples, plus the action-reaction mistake to avoid.French 2Passé Composé: Avoir vs Être and DR & MRS VANDERTRAMPChoose avoir or être in the passé composé with the DR & MRS VANDERTRAMP list, handle agreement, and avoid the most common mistake.ChemistryPeriodic Trends: Atomic Radius, Electronegativity and Ionization EnergyLearn how atomic radius, electronegativity and ionization energy change across and down the periodic table, with two worked examples.BiologyPhotosynthesis vs Cellular Respiration: Equations and DifferencesCompare photosynthesis and cellular respiration: the equations, where each happens, what goes in and out, and a common misconception.CalculusThe Power Rule: How to Find a DerivativeUse the power rule d/dx xⁿ = nxⁿ⁻¹ to differentiate polynomials, with two worked examples and the mistakes students make most often.Spanish 2Preterite vs Imperfect in Spanish: Rules, Trigger Words and ExamplesPreterite or imperfect? Learn when each Spanish past tense is used, the trigger words that give it away, and two worked examples.BiologyPunnett Squares: Genotype and Phenotype Ratios ExplainedFill in a Punnett square, read genotype and phenotype ratios, and avoid the mistake of thinking offspring must match the ratio exactly.GeometryThe Pythagorean Theorem: Formula, Triples and ExamplesUse a² + b² = c² to find a hypotenuse or a missing leg, learn the common triples, and avoid the mistake of adding instead of squaring.Algebra IThe Quadratic Formula: Steps, Discriminant and ExamplesSolve quadratics with the quadratic formula, use the discriminant to predict the answers, and avoid the two most common mistakes.English 10Semicolons vs Colons: Rules, Examples and Common MistakesLearn when to use a semicolon and when to use a colon, with simple tests and example sentences.Spanish 1Ser vs Estar: DR. ROPPMEET, CLEPPP and ExamplesSer or estar? Use two memory tricks, DR. ROPPMEET and CLEPPP, to pick the right verb, with worked examples and a common mistake to avoid.Algebra ISlope and the Equation of a Line: y = mx + b Step by StepFind slope from two points, write a line in y = mx + b form, and avoid the subtraction-order mistake, with two worked examples.GeometrySOHCAHTOA: Sine, Cosine and Tangent Explained with ExamplesRemember sine, cosine and tangent with SOHCAHTOA, choose the right ratio, and solve for a side and an angle in two worked examples.Algebra IISum and Difference of Cubes: Formulas, the SOAP Trick and ExamplesLearn the sum and difference of cubes formulas, remember the signs with SOAP, and factor two worked examples step by step.EconomicsSupply and Demand Shifts: What Happens to Price and QuantitySee how shifts in demand and supply change equilibrium price and quantity, and avoid mixing up a shift with a move along the curve.AP StatisticsZ-Scores and the 68-95-99.7 Rule: Formula and ExamplesCalculate a z-score, interpret it, and use the 68-95-99.7 rule for normal distributions, with two worked examples and a common mistake.