How to Stop Making Stupid Mistakes on the SAT/ACT

One of the most common questions I get is How do I stop making stupid mistakes?

It's a question that's always borne out of a sense of frustration (Arrghh, careless errors keep sabotaging my score!) and a sense of disappointment (I was so close...If only...).

But if we look closer at why we feel that way, it's not just that we're making mistakes, it's that we don't know how to prevent them. If we get a trigonometry question wrong, we can study up on trigonometry, but if we make a stupid mistake, what can we really do besides blame ourselves? We're helpless. Teachers and friends have told us to "be more careful" but what good is that? We thought we were careful enough during the test, yet those mistakes still happened.

Part of the problem is that we're looking for the wrong thing. When students ask How do I stop making stupid mistakes?, what they're looking for is a magic pill, a single trick that will forever cure them of stupid mistakes.

That doesn't exist.

What I'll describe in this post is my solution to stupid mistakes—the things that worked for me when I got a perfect SAT score and a 35 ACT score. No, it's not a magic pill; it's a long-term approach. It won't cure you of all your stupid mistakes, but it will minimize them.

First Things First

The first thing you have to realize is that most stupid mistakes aren't a result of "stupid moments" or carelessness.

They're a result of you not being good enough.

To prove this to yourself, imagine the SAT consisted only of basic addition (1 + 3 = 4). Would you still be worried about stupid mistakes?

Of course, if it's a high-stakes exam, you would double-check your answers, but your confidence would be sky-high after an exam on basic addition. Why?

Because the test would be so easy!

When you're really good at something, it's almost impossible for you to mess up.

The same applies to the SAT. You might think stupid mistakes are, well, "stupid" because you knew better, but even if you knew how to do the question, that doesn't mean better preparation wouldn't have helped. When you deeply understand the concepts you're being tested on, you know what to look for and what answers to avoid. You know the common mistakes, the traps, and the different ways certain question types are presented. It's these little things that can tell you when you're on the right path and when you're doing something "stupid". It's a sixth sense that you develop.

Think of a child. He uses his fingers to add numbers together because he hasn't mastered arithmetic. In his world, his method is completely valid and leads to the correct answer but in the real world, it's error-prone. You don't want to be approaching the SAT at the same relative level the child approaches basic addition. Instead, you want to approach it with a much deeper level of understanding.

Yea, SAT questions are never going to be as easy as basic addition, and I'm not saying mental hiccups don't happen, but the most effective thing you can do to reduce stupid mistakes is to get better through learning and practice. Mastery is the ultimate safeguard. I don't teach students how to be careful—it's not really something that can be taught—and yet my students always end up making fewer "stupid" mistakes after a month of tutoring. That's because what they think are "stupid" mistakes are actually mistakes coming from a lack of awareness. Once they start seeing the questions through a more experienced eye, the mistakes start to disappear. It's the increase in know-how that makes a difference. Right now, you're probably missing things that a more experienced test-taker would pay attention to.


If we break down what "being careful" really means, a crucial component would be habits—routines that keep you from going astray.

In order to form a habit, you have to force yourself to do it until it becomes a natural thing that you do. Brushing your teeth isn't fun, but (hopefully) you're so used to doing it that it's no longer something you think about. You just do it.

The problem is that initial period of pain and discipline.

Most students are unwilling to work through this period to develop habits that will help them on test day. They go through practice tests carelessly and don't bother to read the questions more than once. They don't write down any of their steps and instead circle answers while they watch TV. I'll do things properly on the real test, they say. No need to put in 100% when it doesn't count. Other students fly through the easy questions and only put in the effort towards the end.

What they don't realize is that focus and attention to detail are habits that need to be developed. If you don't do the right things in your preparation, you won't do them on the real test. Consistency is key. You can't go through the motions in practice and then just magically show up at your best on test day. Good test-taking habits must be automatic. Otherwise they're not habits. How you do your practice tests is how you'll do the real test.

Studies have shown that it typically takes 30-60 days of repeated action for that action to become a habit. In my experience, that period roughly translates to 8 practice tests. If you do 8 consecutive practice tests following the guidelines I outline below, then the right habits will emerge. It's these habits, combined with a mastery of the material, that will eliminate your stupid mistakes.

Before we dig into the details for each section, it's important that I give you a general overview of how to start.

In the beginning, don't worry about timing yourself. Just work on a single section at a time and focus on doing it the right way. Feel free to look up things as you go along, but don't get distracted. All your attention should be on the test.

Having said all that, let's dive in.

1. Math
  • Always read the full question, even when it's long and boring.
  • Write everything down, even steps you do on the calculator. This allows you to troubleshoot faster when something goes wrong. Writing things down also makes you more conscious of what you're doing.
  • For questions that require a diagram, draw things out as neatly and as to scale as possible. I can't even begin to count the number of mistakes I've seen that were made by students who misjudged the size of an angle or the length of a line segment in their very own diagrams.
  • After you find an answer, read the question again to make sure you solved for the right thing.
  • For questions that ask Which of the following..., always read through and evaluate every answer choice. Don't just choose the first one that looks right.
  • If being thorough means you run out of time, the harsh truth is that you're not good enough yet. The SAT gives you enough time. See below for comments on the ACT.
2. Reading
  • The way I got an 800 on reading is by being thorough with the answer choices. Not only did I have a reason for why my answer was right but I also came up with a reason why every other answer was wrong. I did this for every question, not just the questions I had trouble on. This process is time-intensive when you first start, but once it's a habit, you actually end up saving time. The more you practice, the faster you get at eliminating the wrong answer choices. So for the times I was only 70% sure of the correct answer, I could count on being 100% sure the other choices were wrong.
  • Physically cross out the answer choices you can eliminate, starting with the answer choice that's the "most wrong". Put a line through them.
  • When possible, I try to answer the question in my mind before I see the answer choices. This is the single most common habit among students who have gotten perfect scores in reading.
  • Rarely do I answer questions based on memory. I almost always go back to the passage to find the lines that support my answer, even if it's just a glance for confirmation. Main idea questions are the only notable exception.
  • Do the "paired" supporting evidence questions together. If the line references in the answer choices don't align with your answer to the previous question, then you should go back to the previous question and reassess your answer.
3. Writing
  • For every grammar question, mentally call out which grammar rule you're using to answer it. Whether it's subject-verb agreement or a misplaced modifier, attach a concept to the question. If your understanding of grammar is solid enough, you should be able to do this for all but 1-2 grammar-related questions. If you don't make this a habit, you end up relying on your ear too much, which opens you up to a lot of mistakes.
  • If you can't attach a grammar concept to at least 95% of the grammar-related questions, you don't know enough. This doesn't apply to non-grammar-related questions such as those testing vocabulary, transitions, relevance, and supporting evidence.
  • For questions that require you to know more than one grammar concept, mentally call out the ones that are relevant as you go through the answer choices. For example, Answer A is wrong because it doesn't use dashes properly. Answer B is wrong because it's a run-on sentence. Answer C is wrong because it's in the wrong tense.
  • Read the full sentence/paragraph. The trickier grammar questions will require you to read the full sentence to get the right answer. An answer choice that looks right when you read only half the sentence might produce an error in the other half, sometimes far from the underlined portion. To get the tougher transition questions right, you will often have to read the whole paragraph. Don't be afraid to read multiple lines before and after the underlined portion.

By now, you should have a good idea of what you need to do to stop making stupid mistakes. The habits I've outlined above are ones that I personally follow. I didn't just make them up. It took many many months of practice to internalize them, but once I did, I was able to get a perfect score.

Stupid mistakes reflect your preparation as a whole. If you know the concepts and you know how to tackle each question, the answers come quicker and you have more time to be thorough. If you're unprepared, uncertainty inevitably creeps in and so too do the careless mistakes.


I want to take the time here to emphasize how hard the whole process is. Nothing will happen overnight and any significant improvement will take a lot of long study sessions where you squirm in your seat.

This is common.

When I was studying for the SAT, I wanted to pull my hair out so many times, especially when I didn't see results. Sometimes, my score would drop from one practice test to the next. But I hung in there and eventually things started to click, and once the ball was rolling, it wasn't before long I was scoring 1500+.

As someone who has been through what you're going through, I can confidently give you this piece of parting advice: HANG IN THERE. It's worth it.

A Note on the ACT

So far, this post has been geared towards the SAT, but almost everything I outlined applies to the ACT as well. You can apply my SAT Math approach to ACT Math and my SAT Writing approach to ACT English.

ACT Reading is a little different in that it's more of a game of tracking down information. Because of that, process of elimination plays less of a role and you won't always be able to apply the SAT Reading advice I gave earlier. Instead, just find the answer in the passage and move on. Time is of the essence.

The same can be said for the ACT Science section. There's so little time that you just have to find the answer in the passage and move on.

In general, it's easier to make stupid mistakes on the ACT because the timing of the exam is so tight. That's why it's even more important for the ACT that you develop good test-taking habits. Fortunately, it's a more straight-forward exam. So with the same overall approach, you can improve just as much on the ACT as you can on the SAT.