Free! In the never-ending age of social media feeds and 24/7 news cycles, primary sources may as well be unicorns. (We’re willing to bet a good posse of K-12 students have never seen one.) That should all change with DOCS TEACH, a vast collection of documents and teaching activities from the National Archives. The documents list is exhaustive, touching on events from the American revolution to contemporary times. Documents are also categorized by National History Standards, should the assessment trolls come knocking. There’s something here for every era of history teacher. Die-hard history buffs will be charmed by the activity creation tool while those who just want to surf the mandated high points can rely on pre-made (and standards-aligned) activities.