@Needyourhelp - Ah, he also took the ACT - I thought he just took the SAT. Since the ACT has a science section, which he scored high on, that should be fine, unless the school specifically recommends a subject test or you both feel he would score high on the Subject Test. Since the SAT doesn’t have a science section, if a student only took the SAT and wants to major in a science at a UC, the Subject Tests do give the admissions department more information about the student’s academic ability in that area. On the other hand, if you think your child wouldn’t score high on it and it isn’t recommended, it would probably be best not to take the test. You want to give them as much positive information as you can in order to show the admissions people that a student can handle the rigor of the UC system.
The Subject Tests stopped being a requirement for UC applicants starting with the high school graduating class of 2012 apparently in part due to AP scores. But, because the UCs are so competitive, particularly the “top” 6, our kids and their friends were encouraged to take the Subject Tests if they were STEM majors and had taken the SAT, no matter which UC they were applying to, especially if they had any weakness in their applications. The kids usually took the tests after they completed their AP courses for that particular course of study. One of my kids, due to her schedule, took Honors Chemistry instead of the AP one. She felt that looked odd on her record since most of her peers took the AP class, so she took the Subject Test for it to prove she could handle the material.