Five young blond and light brown-haired girls are sitting on the ground reading books together.
Five girls taking turns reading aloud for a school assignment
Girls reading books together don't necessarily imply they are reading aloud for a school assignment.
You can read and it not be for a school assignment. You can read a book with another person and not be reading aloud.
Girls reading together are not assumed to be taking turns reading aloud for a school assignment.