Good for you. That can be a great experience for the kids. And you have a place for the chicks. A lot of people forget that step when they do something like this.
You might call your county extension agent. There is a good chance he/she can help with a lot of different things, expert help, equipment, fertile eggs, or maybe even a grade-appropriate curriculum. This goes on all across the country.
One problem you might find hatching at school is that the building is shut down over the weekend. That not only gives problems with turning but the heat and air may be turned off. Hopefully the electricity will at least be left on. Some incubators just don’t handle the temperature swings you might see very well.
Turning is important the first couple of weeks, especially the first week. Turning helps the body parts form in the right place. You don’t want two eyes forming on the same side of the head or if the internal organs don’t form in the right place the plumbing just doesn’t get hooked up right. Also, if the yolk or developing chick comes into contact with the inside of the egg shell it can get stuck. By 14 days or so the body parts have formed and a membrane has developed to protect the chick from the side of the egg shell, so they really don’t have to be turned after 14 days, but early in it is really important. I’d find a way to get an automatic turner.
It’s not that unusual for the eggs to hatch either early or late. I’d suggest starting them on a Wednesday to give you the best chance of them hatching when the kids are there.
