Although Gagne’s original formulation of science as a collection of content-free process has largely been rejected by science educators, its legacy persists in both policy and practice. Many textbooks and curriculum documents still have separate sections on scientific inquiry, science processes, or “the scientific method.” Many classroom teachers follow the lead of these resources, teaching skills and inquiry techniques separately from the conceptual content of their courses.
Other approaches to guiding curriculum include writing national, state, and district science standards. These standards are an important start (at codifying values), but they generally were based on values and the personal experiences of their writers rather than research on children’s learning or detailed conceptual analyses of scientific knowledge and practice. Current national, state, and district standards do not provide an adequate basis for designing effective curriculum sequences for several reasons. First, they contain too many topics without providing guidance about which topics may be most central or important. National standards such as the National Science Education Standards (NSES) (National Research Council, 1996) or Benchmarks for Science Literacy (American Association for the Advancement of Science, 1993) do help to pare down the number of science topics to be covered. However, they still retain many more topics than can be covered and do not identify the most central or important topics. For example, a comparison of the NSES with curriculum in high achieving countries that participated in the Third International Mathematics and Science Study (TIMSS) reveals that the NSES call for much broader coverage of topics with little sequencing across grades (Schmidt, Wang, and McKnight, 2005). Second, they typically present the key ideas as simple declarative statements without explaining how those understandings need to be grounded in experience with the material world or in reasoning practices. Third, they are not sequenced in ways that recognize research on the development of children’s understanding. Project 2061’s Atlas of Science Literacy (American Association for the Advancement of Science, 2001) does provide a guide for interconnection between important concepts in science with some sequencing. The analysis is based primarily on the structure of knowledge in the disciplines of science with some attention to what scientific ideas children can understand at a given grade level. We propose a sequencing that is more deeply informed by research on children’s learning such that the sequences are grounded also in what we know about the ideas children bring to the classroom that can form the foundation for developing understanding of scientific ideas. As we explain later in the chapter, these foundational ideas sometimes do not closely resemble the scientific ideas they can support.