The issue of dissection of animals is easily solved in HS. There are
virtual dissections available on the web, and according to some research I
have seen, they work very well. Indeed it is possible they might work
better than real dissections. There is some evidence that simulations work
better than physical experiments. So it is possible to give the students
with moral objections a choice. But in college dissection is really a
necessity, so if the student wants to be a biologist, they have to dissect
animals. After all they can choose a different major. But in HS biology is
often mandated, so reasonable accommodations should be available. Indeed
the laws and courts have generally mandated "reasonable" accommodations.