Developmental psychology degreeWatch
As interrobang mentions, its worth noting that different unis specialise in different areas of research, and whilst all psychology degrees will cover developmental psychology to some extend, some may offer more extended modules in developmental research areas. Finally you can also do your dissertation in developmental psychology.
Its also worth noting that pretty much all of psychology can be studied developmental. So even topics in "cognitive psychology" such as memory, attention, executive functions, theory of mind; they all also have developmental research into them, and its worth studying these topics even if you want to only do developmental psychology after uni.