I take a week in the spring, one in the summer, one or two in the fall and I have never had a problem, even though my group changes. They come back eager to get into their routines again. My trick is that we go to the library every Monday morning for story time and playing with their toys,then home for lunch and nap. They expect that trip on the first day back after the weekend. Every afternoon at snacktime I talk to them about what we are going to do tomorrow. They always know what to expect, a craft day or a travelling day and they come in excited every morning. It works great for me.