My Daughter was experiencing the same this time last year. But don't worry, the girls will get used to it sooner than you realize it.
Specially the first term is quite busy, there will be assessments in next couple of weeks( No prep required for these) & then the November Exams. Spring Term will be much more relaxed. Of course, this is based on my daughter's experiences.
Homework will keep her busy this term, but that may be due to the transition from Primary to Secondary. Getting used to the new timetable, changing rooms for every lesson, having their own lockers , she will start enjoying all this. All girls feel this pressure & soon sail through