Seeking smaller preschool for shy 3 1/2 year old

I have a 3 1/2 year old daughter who is quite shy. When she's warmed-up, she's very talkative and social, but she's usually very withdrawn in new situations, particularly with lots of noise and people. When we go to parks, she's afraid to go on play structures with other kids, and when we are in novel social situations, she'll mainly want to sit on my lap. I had her in a large preschool that was too overwhelming for her, and recently took her out, because she seemed so sad and withdrawn there. I'm looking for a smaller, more managable setting that would work better for a shy child.

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I also have a shy (slow-to-warm)3.5 year old girl and am looking for similar preschool. I am thinking that small class size is one very important feature, but haven't found any that feel right yet. Would love to talk more with you about this, maybe even have a playdate for our shy 3.5 year olds and any others out there. Please email me if this interests you. We live in North Oaklnd/Rockridge area. Feeling like Flypaper Mama