And we watched older children at circle time, studying the animals under the sea — the octopus has eight legs, the sea turtle is a reptile. They could all read, they were all comfortable in English. More than that, they were clearly comfortable in the classroom; they knew all the subtle rules of classroom conduct, like making eye contact with the teacher, raising their hands to answer, giving their answers in complete sentences.

As we walked through the bright hallways, decorated, like day care and kindergarten hallways everywhere, with personalized cubbies (all the names here in English and Mandarin) and children’s art, we could hear much more raucous noises coming from the gym where groups of children were presumably engaging in more physical — and more chaotic — activity. All the classroom schedules featured playtime, built into the day in carefully programmed increments.

But in showing us circle time, what the school was showcasing was something far more curriculum-based and far more instructional than anything my own children experienced in their years of day care. In fact, the people running the kindergarten acknowledged that parents in Shanghai are deeply aware of the competitive nature of the educational system for which the children are being prepped — and expect them to emerge ready to take tests and excel.

I knew that some of the college students would have concerns about whether what we were seeing represented early academic pressure on very young children. But I also knew that my students were impressed — and so was I.

The classrooms were cheerful, the teachers were positive, and the children seemed to be engaged in the back-and-forth of learning. Yes, the 2-year-olds sometimes seemed to be speaking English sentences they had memorized, without necessarily completely understanding them — but that’s also a part of how children learn language, and they were clearly enjoying shouting out the words together. And the older children — the 4- and 5- and 6-year-olds — understood what they were saying well enough to be making jokes and even teasing their teachers.

When my own children were in day care, all those years ago, I never yearned after curriculum — I just assumed that my children would read on schedule, and read well, that they would learn math just fine when the time came (by the way, the Shanghai day care center told us proudly that it follows the Singapore math curriculum, which produces much better results than our methods in the United States.) But watching the process of deliberately creating bilingual 5- and 6-year-olds, taking full advantage of that remarkable developmental window that helps children learn fluent language in those early years, I felt downright wistful.

To speak a second language from childhood is to have a more capacious brain and a larger connection to the world. I never aspired to having young children who were prepped for testing, or who had been drilled to get a jump on elementary school subjects. But I looked at the way those 2- and 3-year-olds navigated a second language, and I wondered whether I could have done this for my children — or found them a setting that would do it.