Examples of initiatives in crowdsourcing for education that provide exchanges of complementary knowledge. 
- StackOverflow
- ClassOverflow
- Xpress
- Khan Academy Longterm Research

Examples of Exchanging Complementary Knowledge with Crowdsourcing for Education

Crowdsourcing allows the learner to get support from the crowd. The crowd can provide solutions to problems, hints to learning, and even menotring to a learner. 

San Jose State University

- Creating educational contents (resources)
- Providing practical experience (activities)
- Exchanging complementary knowledge (support)
- Augmenting abundant feedback (evaluation) 

Crowdsourcing use-cases in education

Jiang, Y., Schlagwein, D., & Benatallah, B. (2018). A Review on Crowdsourcing for Education: State of the Art of Literature and Practice. PACIS, 180

A Review on Crowdsourcing for Education: State of the Art of Literature and Practice

Crowdsourcing is used to produce educational content or resources. This is a cost and time effective alternative to publishing and other traditional methods of educational content production. It is also a typically a better alternative, in terms of content quality, to using language models to produce similar content. 

Creating Content in Crowdsourcing for Education 

Crowdsourcing uses learners to take part in activities that are too challenging or complex for traditionally crowdsourced groups. Because these tasks often require domain specific expertise, the crowd acquires "industry strength" or "state-of-the-practice" experience. 

Providing Practical Experience through Crowdsourcing for Education

Crowdsourcing is used to provide assessment and feedback on learning. Because of large-scale enrollment and the challenge of providing feedback to scale, crowdsourcing can be used to provide more feedback and assessment. It also has the benefit of potentialy providing better quality feedback and assessment as the crowd provides better diversity in perspective. 

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