Turns out it was against the law, according to state officials.
In an advisory opinion, the Minnesota Department of Administration agreed with a parent who complained that posting her son's test results in class for all to see was a violation of state law protecting student data...
According to experts in education law, it's generally OK for schools to announce who makes the honor roll or graduates with the highest class rank. But revealing a student's grade on a class test in math or history -- without written permission -- is a no-no...
Now let me put on my "old guy" hat and prop my feet up and tell you how it was in the old days. In math class in the 1950s we were given a mimeographed page with 100 addition, subtraction, multiplication, or division problems (simple ones: 8x4, 9x3...) and had I think 3 minutes to do them all. Then you passed the page to the left for a classmate to grade. Then the scores were posted on the bulletin board. Not the best scores, mind you, as in the case above. All the scores. With names. Scores over 90 were in blue, those below maybe 75 were in red. The tests were repeated over and over and over again, and everyone's results were there for everyone to see.
In the 1950s the concept of "team spirit" in the math classroom had not been invented yet. But people sure did learn their basic math.
There's more discussion and explanation of this case at the Star Tribune.
Addendum: Just found a multiplication test (to 12s) on the 'net.
You are given five minutes to complete the table. I found myself slowed down by not being able to touch-type numbers.