How do I choose a good preschool?

What to look for, in one sentence

Look for a program where children choose, play, talk, focus and help each other, with warm adults, whatever the label on the door.

That's the lesson from the best preschool research. At 3 and 4, the skills that matter most for school are built through talk, play and self-control. When kindergarten teachers rate readiness, being rested, able to say what you need and curious come far ahead of reciting letters. Our page on what your child should know before kindergarten covers that survey.

Step by step

1. List the realistic optionsShortlist programs you can reach and afford, and check each one's licensing, ratio and group size.
2. Visit on a normal morningSkip the open house. Stay at least 30 minutes and watch what children actually do.
3. Use the checklistLook for child-chosen play, teachers asking real questions, more child talk than adult talk, daily outdoor time and calm rules.
4. Ask the key questionsAsk about the daily schedule, discipline, teacher turnover, training, and how they handle toileting, naps and allergies.
5. Watch your child after startingAfter four weeks, does your child look forward to going? Their mood at pickup is real information.

What two big lottery studies found

Tennessee: a warning about quality. A state pre-K program was tested with a real lottery that began with about 3,000 children from low-income families, randomly offered a place or put on a waitlist. By sixth grade, the children who got pre-K were doing worse on state tests and had more discipline problems than the waitlisted group. The researchers pointed to program quality and suggested less time on simple skills like letter recognition and shapes, and more on listening, problem-solving, attention and self-control.

Montessori: a promising result. In 2025, Angeline Lillard's team reported a national lottery study at 24 oversubscribed public Montessori schools, with 588 children. By the end of kindergarten, children who won a place were ahead in early reading, executive function (attention and self-control), short-term memory and understanding other people's minds. Vocabulary and math didn't differ. There was no difference after the first or second year; the gap appeared only by the end of year three.

Fair caveats: only about 21% of families contacted agreed to take part, lottery winners were more likely to say yes, results so far stop at kindergarten, and Lillard is a leading Montessori researcher. The name "Montessori" isn't trademarked, so ask about teacher training. Still, it's one of the strongest preschool studies we have.

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Your preschool visit checklist

Visit during a normal morning, not an open house. Stay at least 30 minutes.

• Children are busy and mostly choosing their own activities: blocks, pretend corner, art, books, sand or water.
• Teachers kneel to talk with children and ask real questions ("How did you build that?").
• You hear more children's voices than adult voices.
• Little time in whole-group sitting; worksheets are rare or absent.
• Outdoor time every day, in most weather.
• Rules are taught calmly. No shaming, no long time-outs.
• Staff have stayed for years. Ask about turnover.
• You know the child-to-teacher ratio and group size, and they match your state's licensing rules.
• They can tell you how they handle conflicts, toileting, naps and allergies.

Red flags

Play itself is a green flag. A 2018 American Academy of Pediatrics report on play describes how play with adults and peers builds language, social, emotional and thinking skills, including executive function. Our page on why pretend play matters explains what the research does and doesn't show.

Questions to ask before you sign

1. "What do the children do all day?" Ask for a typical schedule. Look for choice time, outdoor time and short group times.
2. "How do you handle a child who hits or melts down?" You want to hear calm limits, comfort and teaching, not shaming.
3. "What's your ratio and group size?" Then check them against your state's licensing rules.
4. "How long have your teachers been here?" Low turnover means children keep their trusted adults.
5. "How do you work on early reading and math?" Good answers involve games, stories, rhymes and counting in real life, not worksheets.
6. "What training do your teachers have?" Especially important for any program using a named method like Montessori.

For the skills a good preschool builds, see how to help your preschooler build self-control and focus.

The birthday question, and the first week

If your child's birthday is close to the cutoff, you may wonder about waiting a year. In Denmark, researchers compared children born just before and just after the school-entry cutoff, about 54,000 children at age 7. Starting school a year later was linked to a large drop in parent-rated inattention and hyperactivity at 7, still visible at 11. Denmark has high-quality universal pre-K, so the extra year was a good year. Where the alternative is no program at all, the math may differ. Talk it over with your preschool teacher and pediatrician. There's no single right answer, and the decision says nothing about how bright your child is.

For the first week, keep play in your pocket. In a small experiment cited by the AAP, preschoolers anxious about starting school were randomly assigned to 15 minutes of play or to listening to a story. The play group showed about a twofold drop in anxiety.

Go deeper

Grow a Genius

In the book: Chapter 26: Getting Ready for School Without Flashcards

The chapter includes the full preschool visit checklist, the honest story of the Tennessee and Montessori studies, and a school-ready week you can run at home whatever program you choose.

• The 7 Genius Builders, stage by stage
• 16 printable guides, including the Prenatal Label Decoder
• Built on 500+ sources from 35+ countries
• 90-day Double Guarantee

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