Do I have to take Calculus II to take Calculus III?

No, you do not. Some students will be placed directly into Calculus III, because of their AP scores or previous class work. Students in Calculus I who receive a grade of B or better in Calculus I, will be allowed to go directly into Calculus III. Students in Calculus I who do not receive a B or better must take Calculus II before taking Calculus III.