MCAS common mistakes
MCAS · Understand the traps and how to avoid them.
On an ELA multiple-choice item, the student selects the option that is true in real life or matches a keyword from the passage, rather than the option the passage actually supports; in open responses they give a general opinion with no cited evidence.
Familiar topics invite skimming. Recognition of a topic word feels like comprehension, and prior knowledge is faster to retrieve than re-reading a dense paragraph under time pressure.
What to do instead
Use a 'prove it' routine on every item: before marking, physically point to the sentence or line that makes the choice correct, and eliminate any option you cannot locate support for. In open responses, quote or paraphrase two specific details and add one sentence per detail explaining what it shows.
The student answers only the first half of a two-part prompt - explaining what a metaphor means but not how it shapes the passage's tone, or giving a claim in an essay with no analysis of the evidence.
Prompts are read once, quickly, and the mind locks onto the first task verb it sees. Multi-part demands also require holding two jobs in working memory while writing, which is effortful.
What to do instead
Before writing, underline every task verb and number the demands (1, 2, 3). Draft a one-sentence thesis, then check the finished response against the numbered list and add a sentence for any demand not explicitly addressed.
In a text-based essay, the student retells or summarises the passage - 'The author talks about…' - instead of making a defensible claim and analysing how the author's choices develop it.
Summary is the default mode of a reader who understands the text but has not been taught that analysis requires a claim about technique or purpose. Narrative passages especially pull students into retelling.
What to do instead
Write the thesis before the introduction body: one sentence naming an author's choice (word choice, structure, figurative language, evidence used) and its effect. Each body paragraph then pairs one quotation with two sentences of commentary that name the technique and explain the effect on the reader.
On a mathematics constructed-response item, the student writes only a final answer with no visible steps, so a correct answer earns partial credit and a small arithmetic slip earns none.
Years of multiple-choice testing train students to treat the answer as the only product. Constructed responses also feel slower, and students fear showing a wrong step.
What to do instead
Practise against the released scoring guide until the habit is automatic: write the given information, the equation or strategy, each step, and a closing sentence that states the answer with units and explains why it is reasonable. Treat the reasoning sentences as required content, not decoration.
The student solves correctly but answers the intermediate quantity instead of the one asked for - finds x when the question asks for the perimeter, gives a unit rate when asked for total cost, or reports a raw decimal for a money or people context.
The last computation performed becomes the perceived answer. The question sentence is read first and then forgotten while the algebra takes over.
What to do instead
Read the final question sentence first and write the target quantity at the top of the workspace (for example, 'find: total cost, in dollars'). Box the answer with units and check it against the context - no fractional people, no negative time, sensible magnitude.
The student leaves multi-part items, table completions, and 'explain your reasoning' boxes blank, or answers only part (a), even when partial credit is available for each part.
Blank space feels safer than a wrong answer, and a long item looks like a single all-or-nothing task. Time is hoarded for later items that are often just as hard.
What to do instead
Treat each lettered part as a separate scorable point: answer (a), then (b), then (c), even briefly. Budget time so every item receives at least an attempt, and use the last five minutes to return to blanks - an unshown attempt can earn credit; an empty box never does.
In a science investigation item, the student identifies the wrong variable type - naming the dependent variable as the independent one, or treating a controlled variable as a second independent variable - and cannot explain why a control group is needed.
The words 'independent' and 'dependent' are learned as labels, not as roles in a causal test. Students also read the procedure as a story rather than as a designed comparison.
What to do instead
Rewrite each investigation as 'If [what the experimenter changes], then [what is measured], because [mechanism].' Build a three-column table (changed, measured, held constant) before answering, and justify the control group by naming the alternative explanation it rules out.
On a science or engineering item, the student names a concept as if the name were the explanation ('because of density', 'because it has more energy') or proposes a design solution without connecting it to the stated criteria and constraints.
Vocabulary is what gets memorised and rewarded in class, so it feels like a complete answer. Students also skip the design brief's constraints when the problem scenario is long.
What to do instead
Finish every explanation with a mechanism sentence: what happens, to what, and why that produces the observation. For design items, list the criteria and constraints from the prompt first, then state the chosen feature, the trade-off it accepts, and the evidence or test that would show it works.
In history and social science, the student quotes or paraphrases a document and stops there, with no sourcing, context, or connection to the question's historical reasoning - or writes everything known about the era regardless of what the prompt asks.
Documents are treated as answers to be copied rather than as evidence to be interpreted. The prompt's reasoning demand (cause, consequence, change, continuity, comparison) is invisible next to the rich content of the source.
What to do instead
For every source, note author, date, audience, and purpose before writing, then use the frame 'This source shows ___ about ___ because ___'. Re-read the prompt and label which reasoning skill it demands; every paragraph must serve that skill, not just the topic.
The student confuses chronology and context - placing events in the wrong order, attributing a policy to the wrong decade, or judging historical actors by present-day categories and values instead of the beliefs and conditions of their time.
Dates are memorised as isolated numbers rather than as a sequence with causes. Presentism comes from using today's assumptions as the unexamined default framework.
What to do instead
Build a running timeline for each era with causes above the line and consequences below, and place every new event on it. When evaluating a decision, first write what the actors knew, wanted, and feared at the time, then assess the decision against those conditions.