Got to visit some preschools / play schools in 2014 and 2015. My daughter turned 2 this year.
Learning Garden Montessori School along Aguirre when they had an open house. They have an infant class and a casa / preschool class. We found parking space just fine and went to the back of the building where the preschool was. For infants / before preschool age, the playgroup meets everyday for 2 hours and tuition is 6-7k/mo. I think it's about the same for preschool. At the time, my daughter (just under 2) got to try out the preschool room and she really enjoyed having all these activities to choose from on the montessori shelves. It fits with her personality and age somewhat then to really have independent play and you're just there for support. The student teacher ratio is small <10 or <15.
So the preschool area is this big room with all the montessori shelves out, with globes, and puzzles and all. There's a private bathroom and a separate area for meals with kid-size tables and chairs. The staff set a placemat for her use.
Cambridge ATC has been mentioned many times. We were fortunate to go for a 3-day trial. They have a good teacher:student ratio 1:6. And especially for younger kids, the classes don't fill up that much, I think. They always have songs, art activities, and snacks are included, so you don't have to worry about preparing a healthy baon. The space is laid out as 1 big open space with waist-high partitions separating each "classroom". There's a spacious romp area in the center. At each session, they let them wash their hands before eating, brush teeth after eating, and change clothes at the end of class. My nephew went to their Shaw branch and now attends kinder at Lourdes School and his parents are quite happy with how Cambridge helped prepare him. Tuition per year comes to around 100k for 3x/week.
Infants and Toddlers Discovery Center Their banner says they take students 6 months up to 6 years. They have dedicated classrooms per age group and classes meet everyday. Tuition is around 50-60k for the whole school year. There's a main teacher and 1 assistant and about 6 students. When we tried the class, all the guardians were also inside the classroom, so I felt it was crowded. If it were just the kids inside, it might have been just fine. There's also a bathroom right inside the classroom. It was fun with all the action songs, teaching the kids to respond to their names, and of course, there was a selection of toys. Not that many, I think, in comparison to what I saw from the other schools.
Mindbuilders I'm not sure what their parking situation is, exactly, since it's along a busy street. Anyway, when you get inside, there's a 'waiting room' closed area with some toys where you wait I guess if you come in too early for class or wait for sundo. The room felt crowded for the maybe 8-10 kids that were there, but maybe that's just me because I'm big. For the 2 year olds they were teaching the alphabet song I think and the days of the week. It felt somewhat more traditional and like a proper class as compared to the others mentioned here.
Toddlers Unlimited located at 4F Festival Mall. They have a progressive approach and have spacious classrooms with lots of toys for the kids divided into science area, dramatic play, books, manipulatives, etc. There's also a romp area that's like an indoor playground with slides, play gym, etc. There's an option to go 2/3/5x a week. Tuition for 2x/week is about 50-60k/year and 5x/week is about 100k. They wash their hands before eating and have story time, art time, circle time, romp. Their student ratio is good. For the 1 year olds, 2 teachers to 6 students. For the 2s, 3 teachers to 8-12 students. They also have preschool and up to grade 1 or 2 now, I think. It's very clean, the students and any grownups take off their shoes before going inside the classroom.