I would actually check out some teacher blogs and other teacher generated information before going to professional journals.  There is much to be gained from classroom blogs and also personal blogs that serve as reflection about the teaching and learning process in first grade. I think that reading these tales from the front can be more helpful than so- called professional journals for a variety of reasons.  The most foundational would be that it is an authentic voice of experience.  In teaching, the educational journals are a part of the learning process, but they cannot substitute for the petri dish of the classroom and all the variables that go with it.  Additionally, I think that there is something powerful in viewing teachers as not only educators, but actually as teacher- practitioners.  These professionals live at the hyphen and conceive their classroom as constant arenas where theory meets practice and where individuals can help to view their own practice as valid research.