50 Cent -- I'm a Debt School Graduate ... On the Cheap!

50 Cent ... is all boned up on debt -- he just completed a court-ordered class, and got a sweet deal on it too.

As part of his bankruptcy case, 50 was required to take a Debtor Education course ... which we're told he took online. Understandably, they don't charge students a helluva lot -- Fiddy laid out $15 for it.

50 completed the educational portion of the case. Next up for him ... the actual debt repayment plan. That one's not so cheap.