Related Clues:
- B sharp, for one
- Something to take in class
- Something written in class
- It may have many X's and O's
- 'Do,' e.g., but not 'don't'
- Message school sent back
- F-sharp, for one
- Copier option
- Line on a card, perhaps
- Do for one!
- Sticky item in an office
- Cocktail napkin jotting
- Some secret, one turning up in short letter?
- Piece of music?
- Piece of a piece?