Possible Clues:

• Greek letter used as summation sign
• Conclusion reached by Aristophanes, Sophocles, and Euripides
• Bring up a girl, briefly inculcating good character
• Author returns to pen good, classical letter
• Scylla's head?
• What it all adds up to in Greek?
• Greek character's mark of disgrace, with time passing
• Leader of Sparta is to return, having fed endlessly
• Mathematical symbol: short symbol written by scholar
• Little time to avoid damage to reputation for Greek character