With a new experimental section tucked in following its Science section, the ACT will require an additional 20 minutes of testing time starting this September.
It's not unusual for experimental questions to be included in standardized testing in order to try out new question types, gauging student performance and likelihood of correct or incorrect responses. This method of "testing" the test questions is designed to ensure statistical validation and reliability. The SAT too had long utilized experimental questions during test administration, currently providing their experimental section to students who forego the optional essay.
Testing Out the Test Questions
While responses to experimental questions do not count for or against a student's total score, test takers need to be aware of the extra time -- and additional stamina -- required to get though a 3-hour and 35-minute test, soon to be an additional 20 minutes longer. While the ACT has displayed a modicum of courtesy in placing this section following the four main sections, including Reading, Math, English and Science, students who are signed up to take the essay portion need to save up additional energy and focus for this last piece at the very end.