Do mechanical pencils cause problems on standardized tests?

Question

AP Exams are standardized tests that are given at the end of a school year to high-school students that have studied material at a college level. The first part of an AP Exam is the multiple choice section, which is completed and sent to a place where it is graded by a machine.

The PSAT, SAT, and ACT are also standardized tests that have multiple choice tests that are graded by machine upon completion.

All of these tests recommend (or mandate) that the test-taker use a wooden number two pencil and NOT a mechanical pencil when taking the multiple choice portion. For example, from the site describing procedures for the SAT:

Here’s what you can do to make sure your answer sheet is scanned accurately: (...) Use a No. 2 pencil and a soft eraser. Do not use a pen or mechanical pencil.

A large number of students I know and I have used mechanical pencils on standardized tests including the above exams and have never had problems with our tests being graded (I used exclusively mechanical pencils on all of the above tests and have never had an issue in the score).

Are there any instances where a student's use of a mechanical pencil caused a test to be scored incorrectly by a machine? Additionally, what is different between a wooden, number two pencil and a mechanical pencil that justifies the restriction of mechanical pencils?

Answer 1

There are a couple of possible reasons mechanical pencils might be disallowed.

1. Your answers may not be read correctly by the machine

2. Mechanical pencils may be more likely to rip the paper

3. You may try to smuggle in notes or a camera in your mechanical pencil

4. It is easier to fill in the circles with a wooden pencil because it is not as sharp.

From this page: http://blog.prepscholar.com/mechanical-pencil-sat-act We can see that number one is unlikely unless the scanning machine is very old, number two is also dismissed as unlikely, and number four is also an unlikely reason. Number three is also unlikely in practise but the rule leads to the appearance of taking action on cheating and leads people to have more confidence in the tests and the results. They also mention that organisations like testing companies are very conservative and will not change a rule unless there is a good reason.

Therefore: You cannot use a mechanical pencil because it used to cause problems with the scanning of answers and the testing companies can't be bothered to change the rule, along with the fact that it makes their tests seem more reliable as they are seen to be taking action to prevent cheating.