1. It’s always important to point out what students are doing well and to praise any good work honestly. (They can spot overpraise.) The positive comments they get from teachers might be the only praise they receive in a day, for months, or anywhere from anybody. (I was always conscious of that.) Sometimes the former students that stop to say thanks weren’t necessarily the top students, but they likely remember whatever positive comments I gave out.
Which is why I always included creative writing over my 30 year career, so some kids would achieve success and receive positive comments quite apart from their lit crit or essay-writing skills. I even gave 90’s and 100’s for top work, which worked wonders for confidence and self-esteem. (Marks can be used motivationally, especially for non-academic students when used fairly, thoughtfully, and generously.)
2. It is important to have personal contact with as many students in class before, during, and after class. For some kids, this is potentially the most or only social contact they will have with others or empathetic/sympathetic adults in the course of the day. Listening is easily the most important skill any teacher has and can use.