I sympathize but I don't believe any good can come from you approachng the teacher, especially since it is likely that from the teacher's perspective the first quarter is sort of a learning experience so that your DS will have the opportunities to be more careful with the 85% in-class work in general and the 30% map work in particular. High school is quite different from elementary school and it is typical for homework to only count 10% to 15%. It is also not uncommon to have certain categories to only have a couple of assignments. Your situation has happened to my special needs high school DS a few times over the years, but after very careful thought I have always chosen not to advocate. More than half the time, the grades correct themselves for the semester or year. Even though I already have to helicopter my special needs DS, I really did not want to offend the teachers when objectively, their positions were defensible even if arguablly tough on the students.
On the upside, I think this could be a great learning experience for your DS. One of my other child (DS10) ended up receiving his only B last year in health but I think he learned to be more careful. The grade was based only on in-class assignments and there were only about 5 or 6 assignments; he had a solid A average on all the assignments except for one assigment where he forgot to turn over the page to answer the last essay question. After the assignment came back, he even redid the assignment by answering the question he left out and turned it in to the teacher again because sometimes kids are allowed to redo assignments. Unfortunately, the teacher would not accept his redo because he did not actually failed the assignment due to acing the first page. DS was disappointed because his twin had straight A's but it was a valuable lesson that has taught him to take more care with his work. DS is rather the absent-mnded professor at times but he is not 2E so I didn't feel that he was entitled to special consideration.
I apologize if this isn't what you want to hear. If you do want to confront the teacher, your best preparation will be to consider the situation from the teacher's perspective so you won't be caught off-guard by whatever he says. By the way, I think it would be acceptable for your DS to approach the teacher and express his disappointment in missing an A by one percentage point and request help/strategy in earning an A for the semester.
