We have a saying in my family:
Ask a silly question; Get a silly answer.
"It doesn't say spicy"
"I know THAT! It says sardine. ANYONE can see it's talking about fish flavored icecream."
"Mo-ooom!"
"Ask a silly question..."
____
"I don't know how to read."
"Me either. Not a word."
"Yes you do!"
"Pshaw. What makes you think that?"
"You read the menu!"
"Ask a silly question..."
____
Of course, in your daughter's case 1 will get you 20 that she's playing dumb because she's learned to 'play the game'. Socially AND academically. Socially not knowing more than her friends protects her friends feelings AND her social standing with them. Academically it means not challenging an authority figure. Many teachers REALLY hate it when you already know what they're teaching, and react badly. Most though, just pile on MORE work (instead of substituting easy work for harder work). So you not only end up with more to do (dare you; which would you rather; 5 loads of laundry or 15? 5 with a machine, 10 by hand) AND then that also affects your friends' feeling / social standing. At school and with her friends she's protecting herself. With you, she's practicing/ in the habit of protecting herself.