My first thought is that she would see the kids entering the school at 8 (or whatever time) and not leaving until 3 (or whenever) and you could easily point out that they have been at their desks for that time, while she has been playing with her sibling, going for a walk, helping you bake, whatever. We live a little ways away from schools, but have to drive by them whenever we go somewhere, so if it is during the 3 o'clock exodus, I always point out to my kids that those kids have been at school since we saw the bus drive by that morning! It makes an impression. Also, she may have the chance to use the playground when it is NOT overrun by multitudes. That is a bonus to living so close to the grounds. This year my 9 yo dd is taking specials (art, gym, music) at the school, and if we lived across the street it would be so easy! Honestly, unless the school has kids draped out of the windows eating cotton candy and has clowns and ponies walking in the front door it wouldn't even begin to tempt my kids. Even going for the "fun" classes my dd is much happier homeschooling, by her own account!
I remember when mine were your kids ages. It seems like the whole world is geared up to make school seem like the best thing in the world. Every book seems to be about starting kindergarten, or is set in school, and everywhere you go adults seem to be luring kids into loving school. It's everywhere, even if you don't live across the street, if this is the house for you, there are pluses to be found! Good luck!