As a teacher, my job is a particularly interesting in regards to learning students. A typical secondary teacher can easily have 130-150 students each year. Someone once compared this to a doctor or a lawyer seeing 150 patients or clients daily each week. Even if I were spend my entire day, 8 hours, meeting with students individually, the most I could spend with each student would be 200 seconds. And that's assuming no lunch, no bathroom breaks, no instruction, no grading...just meeting with students. In fact, if I limit myself to the confines of the five classes I teach (3.75 hours), I'll only have 90 seconds per student. As you can see, time is short. It's not uncommon for me to learn a student's story, but sadly it sometimes only happens for a select few over the course of the year. The rest simply appear, they do the work, and then vanish each day. Empirically, I know there's more to the students' lives than my class, but you'd be surprised on how easy it is to forget this fact. If a student is lazy on two consecutive assignments, its easy to assume "eh...they're just lazy". If they score poorly, then perhaps I don't think they're that smart. If they're loud, maybe I assume they're annoying. While all of these might be true, it's an unfair assumption based on a sliver of a sliver of their day. The sheer volume of students/patients/clients can be blinding.
What's to be done? It's a hard problem to solve, but awareness goes a long way. Rather than letting ourselves be fooled by a stereotype, or a blanket category, or a gut reaction, it's important to wait. If you wait long enough, and can hold off judging, maybe you'll be able to see the full picture. It may take all year, in fact it may take until your students are delivering their final speeches at the end of their fourth years...but eventually you'll get the full story. It'll be surprising what the narrative reveals.