at DCs school there are four ways to do science at GCSE
for the lowest ability, just to get through the Ebacc, they do Single Science which is modules B1, C1 and P1 of the syllabus
middle ability kids to Double Science which is modules B1, B2, C1, C2, P1, P2
pretty bright kids do triple science in three timetable slots - being B1, B2, B3, C1, C2, C3, P1, P2, P3
the top set do triple science in two timetable sets, allowing them to do another option.
If your child wants to do science A levels, they need to be in that last group.