my story -
My ds was put in preschool bc I was working a couple of days a week and my mom watched my kids and having both of them was a challenge for her bc my dd was just 2 years younger and they would fight. So he went two days a week at age 3 and then 3 days a week at age 4. He made a wonderful transition to Kindergarten and really enjoyed preschool.... so when dd's turn came up we enrolled her in the same place as him. Now, I am home and care for my friend's baby, so Im here for her, but she was rather shy and kind of afraid of groups of kids so it ended up being a wonderful experience for her bc she learned to trust her teachers and meet new friends. She was ready too as she didnt cry the first day I left her..... for a few months going was a bit rocky, but I could see her through the windows and she always settled in nicely and the teachers gave her all the loving she needed.
So this year she will be four in a month and she will go 3 days a week. (mornings).