If it is an elective, taught at the high school level, and taught as historical theology, the study of religion in general shouldn't have any disadvantages.
If it is required, the religious discourse is limited in scope to three religions, and scientific historical evidence isn't taken at face value rather than symbolic value, then there are huge disadvantages.
1) The use of public funds to forward a limited message.
2) A biased view.
3) Lack of historical accuracy
4) Lack of allowance for multiple views
5) Loss of religious context in the course of human progression with regards to polytheism, etc.
Those are just a few.
If it is required, the religious discourse is limited in scope to three religions, and scientific historical evidence isn't taken at face value rather than symbolic value, then there are huge disadvantages.
1) The use of public funds to forward a limited message.
2) A biased view.
3) Lack of historical accuracy
4) Lack of allowance for multiple views
5) Loss of religious context in the course of human progression with regards to polytheism, etc.
Those are just a few.
