9th Grade posters

Literary Terms

The terms high-school essays are expected to use, grouped and defined.

Thesis & Evidence

How to build a defensible thesis, and the evidence sandwich under it.

Close Reading

Four passes over a text, each looking for something different.

Analysing Sentence Structure

What sentence length and shape do to a reader.

Rhetorical Devices in Speeches

Six techniques that turn up in almost every famous speech.

Characterisation

Direct and indirect — and why writers prefer the second.

Symbol, Motif and Theme

Three connected ideas, and how one builds into the next.

Evaluating Research Sources

Five checks before a source goes into a bibliography.

From Notes to Essay

The bridge between having read everything and having written nothing.

Function Notation

f(x) is not multiplication — and everything else follows from getting that right.

Domain and Range

Which inputs are allowed, and which outputs actually appear.

Factoring Out the GCF

The first thing to try, every single time, before anything else.

Factoring Trinomials

Two numbers that multiply to c and add to b — and when a is not 1.

Difference of Squares

The pattern worth spotting instantly, and the one that looks similar but does not factor.

The Quadratic Formula

The method that always works, and the sign errors that ruin it.

The Discriminant

One calculation that counts the solutions before you look for them.

Anatomy of a Parabola

Vertex, axis, roots and direction — everything a quadratic graph tells you.

Choosing a Systems Method

Graphing, substitution or elimination — decided by the shape of the equations.

Arithmetic Sequences

Add the same amount each time, and the formula that jumps to any term.

Proving Triangles Congruent

Five shortcuts that work, and the two that look like they should but do not.

Triangle Theorems

Six rules that solve most triangle questions without measuring anything.

Writing a Geometry Proof

The structure, and the habit that makes proofs writable rather than mysterious.

Similar Triangles

Same shape, different size — and the scale factor rules for length, area and volume.

Function Toolkit

Domain, range, notation and the parent functions with their graphs.

Quadratics

Factoring, the quadratic formula, the discriminant and parabola anatomy.

Systems of Equations

Graphing, substitution and elimination side by side, plus what 'no solution' looks like.

Geometry Reference

Angle relationships, triangle rules, congruence and the proof vocabulary.

Exponential Functions

Growth that multiplies rather than adds — and why it always wins.

Solving and Graphing Inequalities

The same steps as an equation, plus one rule and one new notation.

Absolute Value Equations

One equation, two cases — because distance works in both directions.

Adding and Multiplying Polynomials

Combine like terms to add; distribute everything to multiply.

Graphing a Line Fast

Four points plotted in under thirty seconds, from any form.

Rearranging Formulas

Solving for a letter when everything else is letters too.

Simplifying Radicals

Pulling perfect squares out from under the root sign.

Cell Theory

Three statements that underpin the whole of biology.

DNA Structure

A twisted ladder, and the base pairing that makes copying possible.

From Gene to Protein

Transcription then translation — two steps, two locations.

Photosynthesis and Respiration

Two equations that are almost exact mirrors of each other.

Punnett Squares

Predicting offspring ratios from two parents' genes.

Evidence for Evolution

Five independent lines of evidence, all pointing the same way.

Enzymes

Biological catalysts, and the two things that destroy them.

Homeostasis

Keeping the inside steady while the outside changes.

Cell Structure & Function

Every organelle with its job, plus transport across the membrane.

Periodic Trends

Atomic radius, ionisation energy and electronegativity, with arrows for each trend.

Levels of Ecological Organisation

From one organism up to the whole biosphere.

The Carbon Cycle

Where carbon goes, and where humans changed the balance.

Making a Scientific Claim

Claim, evidence, reasoning — the structure every lab conclusion needs.

Viruses and Living Things

Why virology sits awkwardly between chemistry and biology.

The Nitrogen Cycle

Why the most abundant gas in the air is useless to almost everything.

Managing a Long Assignment

Working backwards from the deadline, and the two hardest days.