All three of our kids went to different preschools, and each of them had a wonderful experience. The best thing you can do is visit different schools, ask for references, and trust your instincts. Don’t just tour the school, but spend time observing the class your son would attend. Look for teachers who interact with the children on their level, provide a structured classroom environment with a balance of free-play and teacher-led activities, daily playtime outside (weather permitting), and age-appropriate expectations. Talk to other parents and see how they feel about the preschools their children attend.
My two oldest went to secular preschools. One was full-time at the daycare center where I worked. It was fantastic, with excellent teachers and facilities. The other went to a small local preschool. I’d heard great things about it, it was low-cost because a large part of their budget came from parent volunteer fundraisers, and the teachers were educated with a lot of experience. My son went two ½ days when he was three and three ½ days when he was 4. It was a great program with a lot of field trips and involvement from parents.
My youngest is currently in his second year of preschool at a local church and goes three ½ days a week. He has absolutely loved it since his first day in the three year-old class. Even though it is a church preschool, the only “churchy” thing they do is say a snack prayer. The prayer is very general. His teacher has been at the preschool for several years, and their reputation is so good that they have a waiting list every year. I wanted my other son to also attend this preschool, but we never got off the waiting list. It was only the addition of an afternoon class that made room for my youngest son because the existing spots were always filled first by families who already had children in the school.
I don’t think preschool is essential, especially if a child has opportunities to spend structured social time with other children. Dance class, karate class, swimming lessons, etc., will give a child experience in large groups before kindergarten. Reading and playing at home will give a child the basic knowledge expected of kindergarten children, like counting to ten and knowing the ABC’s. Preschool is really good for socializing with peers and learning to behave in a school setting. Not essential, but if you can afford it and find a good program, there really aren’t any drawbacks. It really seems that children started kindergarten are expected to be socially ready more than anything else these days, and a decent preschool will certainly accomplish that even if your child only attends part-time.
Also, if a preschool did nothing more than babysit, my kid would never set foot in the door. I worked in a high-quality daycare for several years and have very high expectations for all kinds of childcare, even preschool.