I already know the devanāgarī script. Can I enroll in the Intermediate course?

Not solely on the basis of a knowledge of devanāgarī. The devanāgarī script is an important part of the Elementary course. Students will spend their first year attaining competence in it. But it is just one aspect of a fairly broad introductory course. Elementary Sanskrit provides, in addition, an introduction to all major aspects of Sanskrit grammar. It is absolutely critical that students acquire a strong grammatical foundation in Elementary before attempting the Intermediate course. If a student has a solid foundation, in addition to a knowledge of the script, s/he may enroll in the Intermediate or Advanced courses by successfully completing a placement exam.