This paper systematically reviews the state of the art of the literature and practices of enhancing learning and teaching through crowdsourcing. We refer to these emerging phenomena as “crowdsourcing for education” (CfE). Based on 51 relevant initiatives in practice, which we identified, we develop a definition and a taxonomy of CfE, and analysed CfE following the structure of what, who, why and how. We find that crowdsourcing has been used and benefits education in four ways: creating educational contents, providing practical experience, facilitating the exchange of complementary knowledge, and augmenting feedback. Eight principal motivations are reported to have led people to participate in CfE systems according to existing studies. This paper supports future research by developing a framework for CfE and providing a research agenda.