Conocer means to know [a person], or to recognize [something]. Saber means to know or to have the knowledge of [something].
Example: <span>Él la conoce. - "He knows her." or </span>Yo conozco el carro. - "I recognize the car." Ella sabe dónde est<span>á, - "She knows where it is."
You're talking about knowing which classes you have. Sabes quales clases tienes.