The number of K-12 teachers using digital media is up 7 percent from last year, according to a PBS-funded ongoing study by Grunwald Associates. The research and consulting firm has been tracking educators’ media use for PBS since 2002. Other findings: Of those teachers using digital media in the classrom, 80 percent are frequent or regular users. Seventy-two percent say they stream or download content from the Internet, up from 65 percent in 2008. And PBS content and websites are the top choice for pre-K educators.