Spatial Concept Perspectives We have gathered ~300 excerpts from
published works about fundamental spatial concept terms. These
have been cross-referenced with the concept lexicon appearing on
the left. Those terms were drawn from the U.S.National Science
Education Standards (NSES 1996) for topic areas B - Physical
Science, C - Life Science, D - Earth and Space Science, as well
as from the 1994 U.S. Geography Teaching Standards for grades
9-12. Those standards can be browsed here.