Curated OER
The Colour Wheel
A review of terms associated with the study of color as an element of art: spectrum, hue, color wheel, primary colors, secondary colors, tertiary colors, complementary colors, and analogous colors.
Curated OER
Educational Technology Clearinghouse: Maps Etc: North America, 1885
A map from 1885 of North America and Central America showing the major relief features of the region. The map shows the primary highland known as the Pacific Highland, with the Sierra Nevada and Rocky Mountains, the secondary highlands...