The advent of generative AI has caused both excitement and anxiety among educators. Some school systems have gone so far as to ban it altogether. Generative AI has the potential to transform human learning; but like any new technology, it has both strengths and weaknesses, and adopting it involves some risks. There are risks that generative AI will mislead learners with wrong information, or that learners will use it to do their homework and take tests for them. This article presents some ways to take best advantage of generative AI, while managing and mitigating the risks. It also suggests some uses of generative AI to avoid. These insights are informed by learning science and extensive experience developing AI-enabled learning products. If applied properly, generative AI can dramatically accelerate human learning and do so at scale.