Placement exams are mandatory & almost all schools require you to take it before selecting classes. Keep in mind that placement exams can only be taken once. Placement exams are very crucial because it will help determine the classes you should take base on your knowledge in the subject. For a list of the required placement and optional placement exam, please double check with your school or advisor.
During my orientation I took my English placement exam & did well to place into College English 112. My friend, who didn’t take the exam seriously & slept through it got place in College English 111. After finding out, he was upset because College English 111 wasn’t credited towards a requirement for school & it was a beginner English. He knew the material but because he didn’t take the exam seriously, he had to take the beginner’s class.
Don’t make the same mistake as my friend. Take the exams seriously & try your best. Good luck!