Does progressive education have to mean watered down math?

One of the most common criticisms of "progressive math", aka "reform math", is that the math itself is highly watered down--a natural consequence of the inefficiencies of child-centered discovery learning.

But every once in a while, I'm reminded that there are other incarnations of "progressive education" in which the math is anything but watered down.

My mother, for example, attended a self-proclaimed progressive private school in the 1950s where she got a very solid education in math (not to mention English, French, and history). In fact, a number of the algebra problems I've excerpted in my math comparison problems (comparing traditional U.S. math with Reform Math) came from her algebra book.

Now we have a very interesting article from this week's New Yorker about 3rd grade math at a progressive school in Chengdu, modeled after John Dewey. Here is one of the third grade math problems the author's twin took home with them:

While multiplying one two-digit number by another two-digit number, Little Sloppy misreads 22 as 25, and as a result his answer is higher than the correct answer by 69. What is the correct answer.

How many American 3rd graders can do this problem--no matter how "progressive" (or not) their math classes are?

Two years later, when the family returns to the U.S. but the twins continue to learn Chinese math through a remote tutor, they're doing problems like:

A certain number, when divided by 3, leaves a remainder of 2; when divided by 4, leaves a remainder of 3; when divided by 5, leaves a remainder of 4. What is the smallest that this number could be?

“Math is virtue"; “Math is a way to cultivate yourself," the author quotes the third grade math teacher as saying. 

America's "progressive math" proponents seem to see things differently.