Prepare for the ACT

What to practice: Purpose, relevance, additions and deletions, sentence placement, introductions, conclusions and transitions.

1. Read enough of the passage to name the writer’s goal. A sentence can be true and grammatical yet fail that goal.
2. For an addition or deletion, describe the specific information gained or lost. Match that effect to the requested purpose.
3. For sentence placement, follow references such as “this method” or “these results.” Introduce an idea before explaining or evaluating it.
4. For a transition, identify the relationship first: continuation, contrast, example or consequence. Then choose the wording that expresses it.

Check your work: Point to the passage’s goal before choosing an answer about whether information belongs.

What to practice: Redundancy, word choice, clarity, style and tone.

1. Say what the sentence needs to communicate. Preserve every necessary fact and relationship when shortening it.
2. Remove repeated meaning, such as a verb followed by a phrase that merely defines it. Do not delete a useful qualification.
3. Choose a precise word using the full context. A familiar synonym may have the wrong meaning or grammatical construction.
4. Read the revised sentence beside its neighbors. Keep the passage’s level of formality and check for an unclear pronoun or modifier.

Check your work: Read the shortest choice as a complete sentence; shortest is not automatically correct.

What to practice: Clause boundaries, commas, semicolons, colons, dashes, possessives, agreement, pronouns, verb forms and modifiers.

1. Find the subject and main verb of each clause. Temporarily remove descriptive phrases to reveal the sentence’s structure.
2. Join two independent clauses with a period, semicolon or comma plus a coordinating conjunction. A comma by itself is not enough.
3. Check whether descriptive material is essential to identifying its noun. Nonessential material needs matching punctuation on both sides.
4. Check agreement with the actual subject, consistent verb tense, clear pronoun reference, parallel lists and the owner of each possessive.

Check your work: Explain the grammar rule. A pause in speech or a nearby plural noun is not sufficient evidence.

What to practice: Fractions, exponents, radicals, number properties, ratios, percentages, linear equations, systems, inequalities and quadratics.

1. Define the unknown and record the units. Turn words such as “per,” “at least” and “increases by” into the correct operation or inequality.
2. Simplify in a controlled order: distribute, combine like terms, then isolate the variable. Reverse an inequality when multiplying or dividing by a negative number.
3. For a system, eliminate a variable or substitute an expression. For a quadratic, look for factoring before using a longer method.
4. Substitute into the original conditions. Check restrictions such as a nonzero denominator, an integer count or a positive length.

Check your work: Return the quantity requested, with its units—not an intermediate result.

What to practice: Function notation, domain and range, composition, inverse relationships, linear and nonlinear graphs, polynomial and exponential models.

1. Identify the input and output. For f(a), substitute a everywhere x occurs; for f(x) = a, solve an equation.
2. Use the representation that reveals the needed feature: a graph for intercepts and behavior, a table for a rate, or a formula for an exact value.
3. Track transformations carefully. Adding outside a function changes outputs; changing its input affects horizontal position.
4. For composition, evaluate the inside function first. Check the input’s domain and whether a model is valid in the stated situation.

Check your work: Label each intermediate output and feed it into the next function in the correct order.

What to practice: Angles, triangles, similarity, coordinate geometry, circles, area, volume and right-triangle trigonometry.

1. Sketch or annotate the figure using the stated information. Do not infer equal lengths, right angles or scale from appearance alone.
2. Identify the requested measurement and the relevant relationship: similarity, the Pythagorean theorem, a circle formula or a trigonometric ratio.
3. For coordinates, calculate differences before applying slope or distance. For trigonometry, identify opposite, adjacent and hypotenuse relative to the named angle.
4. Check units and reasonableness. A length uses linear units, area uses square units and volume uses cubic units. Confirm the calculator’s angle mode.

Check your work: Name what every value in your formula represents before calculating.

What to practice: Mean, median, spread, weighted averages, counting, probability, two-way tables and data interpretation.

1. Read graph labels, units and scales. Distinguish a frequency from a proportion and identify the group the question describes.
2. For a mean, work with total value divided by count. Combine groups using their totals, not an unweighted average of their means.
3. For probability, count favorable outcomes and possible outcomes within the same sample space. A condition can shrink that space.
4. Track whether selections are independent or made without replacement. Check that a probability lies between 0 and 1 and that conclusions do not exceed the data.

Check your work: Write the eligible group beside the denominator before simplifying a fraction.

What to practice: Central ideas, explicit details, sequence, comparison, cause and effect, summaries and inferences.

1. Read for the passage’s main development: what changes, what is explained or what claim is supported. Give each paragraph a short mental label.
2. Use the question to return to the relevant evidence. Read the surrounding sentences so a detail keeps its context.
3. For an inference, combine what the passage states without adding an unsupported motive, cause or universal rule.
4. For a summary, select the statement that covers the passage’s main point rather than one vivid detail. Check every part of the chosen answer.

Check your work: Underline the words that support the whole answer, including its degree of certainty.

What to practice: Words in context, figurative language, paragraph function, organization, point of view, purpose and tone.

1. For a word in context, replace it with a simple phrase before examining the choices. Use the surrounding logic rather than the first dictionary meaning.
2. For a sentence’s role, describe its job: example, contrast, explanation, qualification or shift in the argument.
3. Separate the author’s view from a view the author quotes or describes. Track who is speaking and the evidence for their attitude.
4. Choose a tone supported across the relevant text. Strong labels such as hostile or ecstatic need stronger evidence than mild interest or concern.

Check your work: Put your choice back into the sentence and verify both meaning and tone.

What to practice: Paired passages, claims and evidence, fact and opinion, assumptions and connections between text and visual data.

1. State each author’s main claim separately. Preserve differences in scope, conditions and strength before comparing them.
2. Identify the evidence offered for each claim. Ask whether it addresses that claim or merely discusses the same general topic.
3. For paired passages, choose a point both texts support when asked about agreement. Do not transfer one author’s opinion to the other.
4. For visual information, check the measured variable and population. Then test the specific textual claim against the relevant values.

Check your work: Find evidence in both texts for an answer claiming that both authors agree.

What to practice: Data interpretation, axes and legends, trends, proportional relationships, interpolation and translating between displays.

1. Identify the variables, units and key. Work out which quantity changes across a row or axis and which quantity is measured.
2. Find the exact series and condition named by the question. Read values before comparing them; check for an uneven axis scale.
3. Distinguish the size of a value from the size of its change. A larger final value does not necessarily mean a larger increase.
4. Interpolate only under the relationship the question permits. Treat a prediction beyond the observed range as a prediction, not an observation.

Check your work: Keep the estimate inside the stated model and distinguish it from a directly measured value.

What to practice: Scientific investigation, experimental comparisons, controls, replication, design constraints and extensions of a study.

1. Identify the question the experiment tests. Name the independent variable, the measured outcome and the conditions held constant.
2. Choose comparisons that isolate the variable of interest. If two conditions change at once, the result cannot distinguish their individual effects.
3. Read repeated trials for consistency and variation. More observations can improve reliability without correcting a systematically biased design.
4. When extending an experiment, alter the intended factor while preserving a useful comparison. Check whether the proposed result is a measurement, inference or hypothesis.

Check your work: A control comparison must separate the factor being tested from other possible explanations.

What to practice: Scientific arguments, assumptions, agreement and disagreement, model predictions, support and contradiction.

1. Summarize each model using its stated mechanism and assumptions. Do not replace a model’s claims with outside knowledge.
2. Make a short comparison: where do the models agree, and which condition produces different predictions?
3. Evaluate new evidence against each specific prediction. Evidence can weaken a claim without proving every alternative correct.
4. For a useful follow-up experiment, choose a condition that separates the predictions and a measurement capable of detecting the difference.

Check your work: Write both predictions before selecting the observation or experiment.