I also get the cal grant B. Ususally if you qualify for this, you qualify for a PELL grant. I think the PELL grant is the one that covers your tution and then they mail you the Cal Grant B in the mail.
Ususally I just register for classes, its covered (except in Summer), and they send me a check later in the mail. Your school's financial aid website should have a disbursement schedule out telling you when to expect your check.