At my kids’ high school physical science is the default science choice for 9th grade(all kids must take the course). Not really sure why it is this way - there are certainly a lot of kids who could or should take bio . As a result, kids who are strong in math and science typically double up with honors bio/honors chem in 10th grade. As our school doesn’t offer AP before 11th grade, these kids are still able to take AP Physics, AP Chem, AP bio etc.