Possible Clues:

• Betray drowsiness
• Yes, that's the way to make one of what's done
• 10 across returns with Bob
• Would 16 down be frozen with this? It seems, yes
• "Wynken, Blynken and ___"
• Move head in assent
• Yes, that's the difference between 3 down and o'er
• Cain was banished to the land of ...
• Careless mistake member of teaching staff picked up
• That shows one is agreeable to Number Five Hundred