The search engine Gooru offers free educational resources for K-12 teachers and has been launched recently. The participation of education professionals helps to keep up the quality of the content. Digital teaching material is provided by the libraries of various school districts or was sorted, produced and reviewed by a community of teachers all over the United States. The content partner CCST's California Teacher Advisory Council (Cal TAC) developed and contributed a resource guide, including a “QUICK Assessment” checklist. It was designed for use by teachers to determine the quality of digital resoures.