Can RN students take the LPN Exam?

You need to ask this question of your state's Board of Registered Nursing. Then you can ask the administration at your school of nursing. Just because your state allows this does not mean that your school will cooperate. In most instances, a person has to have completed at least 50% of the program, including the accompanying clinicals. It still is in the hands of the school whether or not they will sign off on the application for licensure.

It depends on how your RN program is set up. The program I went through was called a "career ladder" and we were eligible to sit for the LPN exam halfway through but not all programs allow that.