The draft during World War II was conducted through a series of acts passed by the U.S. Congress. The first of these acts, the Selective Training and Service Act of 1940, established a system of compulsory military service for men aged 21 to 35. However, the act also included provisions for deferments, which allowed certain individuals to be exempted from military service temporarily or permanently.
One type of deferment was for college students. The act provided that college students could be deferred until they reached age 22, as long as they met certain criteria. These criteria included maintaining a satisfactory academic standing and pursuing a course of study that would prepare them for a "necessary activity" in support of the war effort.
However, the deferment for college students was not automatic. Students had to apply for deferment and meet the specified criteria in order to be granted one. Additionally, the deferment could be revoked if the student's academic standing declined or if their course of study no longer met the criteria for a necessary activity.
Furthermore, as the war continued and manpower demands increased, the eligibility criteria for deferments became stricter. In 1943, the Student Deferment Act of 1943 was passed, which eliminated the automatic deferment for college students and required them to apply for deferments on an individual basis. Additionally, the act authorized the President to order the induction of college students into military service if they were found to be necessary for the war effort.
So while being in college may have provided a temporary deferment for some individuals, it did not guarantee an exemption from the draft.