We surveyed the use of Great Lakes online learning materials by a sample of K-8 teachers. Analyses tested for correlation of use with 1) whether teachers learned about the resources in pre- or in-service education, 2) geographical significance, and 3) whether teachers taught about the topics emphasized in the online learning materials. We compared findings for the Great Lakes to an ocean resource (BRIDGE) and more general Earth System Science online learning materials. Teachers reported using the Internet for teaching and planning. However, very few teachers reported using Great Lakes materials, BRIDGE, and most of the generalized online learning materials. The exception was the National Oceanic and Atmospheric Administration National Weather Service webpage, used by >50% of respondents. Teachers who learned how to use online learning materials in pre-service or in-service education were more likely to use them in-service. There was no significant effect of geographic proximity to the Great Lakes or ocean on the likelihood that a teacher used particular materials. Teaching about the Great Lakes was a necessary, but not sufficient condition for using Great Lakes online learning materials. The results indicate that teacher education is a key to inclusion of specific online learning materials in K-8 education.