RT James Fishback (@j_fishback)All 50 states would block @elonmusk from teaching a high-school physics class because he doesn’t have a government-issued "teaching certificate." We’ve got professionals and retirees in all 50 states—engineers who built bridges, pilots who’ve flown across the world, and doctors and nurses who’ve saved lives—who would love to volunteer to teach.Yet they can’t because teachers unions have lobbied to create barriers. As Governor, I will tear down these barriers and invite profess ...