Nursing assistant training courses may take anywhere between three weeks to three months to complete, depending on the facility or school which offers the program. To enroll in nurse aide classes you must meet certain admission criteria pertaining to education, health, and background history. Those who are accepted into CNA classes must complete both the classroom and hands-on practice sessions to graduate but training is not required in all states. Finally, one must pass a final exam which tests a candidate's skills and abilities to practice correctly and safely. When you pass this final test you become a certified nurse aide.