Yup. She's ready.
The kindergarten teachers dished out ice cream and politely answered silly/anxious questions like: what kind of backpack is best to get? (Doesn't really matter, as long as you can fit a pocket folder in it) and, Can my mom, who will be visiting and doing childcare that week, ride the school bus with MG on the first day? (No, but she can meet her at school if she wants, and there will be people there especially to make sure the kindergarteners get to their classrooms okay.)
Then MG got to poke around a kindergarten classroom and at the afterschool-care room where she'll be spending a couple of hours most days. (There's a loft! and a hamster!)
A few days later I was putting her to bed, and out of the blue she asked, "What's twenty and twenty?"
So I went on about how twenty and twenty is forty, and it's like two tens and two tens, and she already knows about two and two being four...she tuned out the blah blah and said, "So, it's forty?"
"Okay, now ask me again," she ordered.
"What's twenty and twenty?"
"No! Pretend we're in school and you're the teacher!"
"Um...all right...[*slow and slightly condescending teacher voice, probably not too different from the one I use at work*]: MG, what's twenty and twenty?"
"No!! Not that way!! Ask the whole class!!" She gestured out to the invisible class that apparently surrounded her in her bed.
"Oh-- right--ahem: Class, who can tell me what twenty and twenty is?"
MG's hand shot straight up. I turned my teacherly gaze on her. "Yes? MG?"
"Forty!" she declared.
"Very good, MG," I nodded.
MG lay down and snuggled onto her pillow. "I'm gonna knock their socks off," she murmured happily.