The Learning.com Marketplace offers excellent resources. Some are free, including those from the National Science Digital Library courtesy of the Texas Instructional Materials Exchange (TIME). It includes high-quality,cutting-edge digital resources to help students and teachers interested in Science, Technology, Engineering, and Math (STEM). These are real-world experiences and create excitement for today's digital learners.

To access the resources, create a free account and then search for the National Science Digital Library: http://www.learning.com/texas/time/