Taking Calculus in High School is very different from taking it in college; particularly from a social point of view, especially for AP and Honors courses.
For example, I hear from my students about the egos and social pressure, shaming and boasting that goes on in some of the AP classes. Most of the students already know each from earlier years and thus can be too comfortable playing out certain kinds of immature agendas.
One particularly insidious example is when a student gets a high score, he boasts that he did not prepare for the test, and will offer pseudo-sympathetic words to another student who worked hard, but got a lower score.
Marisa, a senior in High School, started tutoring part way into the second semester, at a time when students often begin worrying about the Calculus AP exam. She was very bright, but had been a target of the situation mentioned above. (Although the braggart did finally confess that he had in fact prepared for the test.)
She was fully capable of passing the AP but her confidence had suffered from a few social interactions, making her nervous to the point of affecting her ability to learn some of the new material in class. I knew it was time for some confidence building !
For example, while working on a problem involving lots of Algebra steps and messy fractions, I just might intentionally make an arithmetic error and ask Marisa to help check my arithmetic. When a student finds my error, it makes her feel good, and I see the pride building.
Or, when she begins to understand the material, turn the tables, and ask her to pretend I don't get it, and explain it to me. I always ended sessions with a list of her wins.