Yes, I would say "I'm fine, thanks, and you."
But I find this all a bit annoying, especially with the parents in the playground. They walk past and say 'How are you?' but there is barely time for a 'fine' before they are out of earshot (if they are going in opposite direcions!). Hello would just be easier. Or Good morning.
NC4now "Well, from what you’ve written, no. It sounds like you are being stand offish." I don't think that necessarily. But she might be. Or she may just like pulling people up on how they speak!
Either she is hard of hearing, so speak up a bit.
Or she thinks you should ask how she is, so do that. But to be honest it seems quite silly, no one really replies how they really feel, do they!
Or get in their first and always ask her how she is first time you see her in any day and note how she replies. *Resist temptation to say 'I'm sorry', (which isn't the correct phrase when you don't hear someone, it should be 'Pardon')!
"Nothing wrong with telling the consultant you’re exhausted, or looking forward to going home, or whatever." I don't agree if one were at work, I think saying you can't wait to get home when you are at work is a bad idea.