Related Clues:

• Barely passing grades
• Two Scottish rivers
• Bad marks
• Low marks
• Odd couple?
• Two of fifty?
• Poor grades
• G.P.A. spoilers
• Rick who sang 'Disco Duck'
• They can make a suer suffer
• Two of diamonds?
• Rotten grades
• This puzzle's surplus
• Detached ends?
• They're in the middle of middle