Some history: In one of my first few years of teaching, I was at an upscale school where the challenging courses were actually challenging. A student in my geometry honors class was debating whether or not to switch to an easier track, and she decided to stay in class. She struggled all year, and I believe ended up with a C. At the end of that year I had the students write a letter to my next year's students telling them various things - what to expect, what to do to succeed, what to study harder than they think they should, etc. The students also put in their own comments on other things. (I would give these letters to the students at the start of the next school year). Well, this one girl in her letter mentioned that she was really happy she had stayed in the class because it proved to her that she could do something challenging. So even though she didn't get a "good" grade, she felt she was successful in this endeavor. This stuck in my mind.
This year I have a couple of students that were debating early in the year whether or not to stay in precalculus preAP. They were struggling and had/have low algebra 2 skills. I told them that I can't tell them what to do, but that as seniors, if they skip a year of math, it will be extra hard the following year in college to get back into it. They both decided to stay. One is doing fine and is coming in for tutoring. The other is still struggling with basic concepts. This morning his mother sent me e-mail basically saying, "I'm sorry he decided to stay in the class as it looks like the rest of the year will be a struggle filled with low grades". That made me sad for her and for him. I wrote back to her about how it would be extra hard the following year in college for math placement exams if he missed a year of math. I suggested tutoring for algebra 2 skills, and she asked for names, so hopefully they'll follow through.