Teachers Pay Teachers represents a growing online marketplace — once dubbed the Etsy of Education — that now has seen 6 million teachers in the past year buy or sell classroom resources. It’s part of an effort to help teachers to help one another create fresh approaches to instruction while getting paid for their work....

The world of 4K microscopes is generally limited to high-level research universities. These ultra-high-definition scopes allow for enhanced detail that make a regular microscope look downright analog. But a push by the National Science Foundation and a nonprofit organization called US Ignite is opening 4K science research for under-resourced high schools across the country, bringing...