Thats a good way of getting into the career, my only word of warning is to say that PGCEs are incredibly competative and therefore you wont necessarily get a place straight after your degree unless you have a 2:1 and above plus lots of experience. Also, it may be worth considering that some jobs may be wanting you to have that GCSE in science so you may have to do it and that the early childhood studies course may not give you enough experience working with children so you may have to do more volunteer work etc outside of the course.