I never taught and don’t plan on starting. However, from a student’s perspective, I can say I strongly disagree with giving over any info past basic family situations (dead parent etc.).
When I was in 9th grade, I was an (almost) failing (read: low 70’s) student. My teachers treated me as a dumb kid, which I’m not. By the time I reached 10th grade, I became much more serious about school, and became a high 90’s student. Had my teachers asked in advance, and heard that I was a dumb, failing student, I would not have had the motivation to try and would have remained a failing student through high school.
For those who do ask, please do your students a favor and NEVER show them that you know ANYTHING. Treat them all equally. Give them a chance!