https://www.brainfuse.com/home/peers.asp

http://www.magazine.utoronto.ca/life-on-campus/donny-ouyang-online-peer-tutoring/

https://peers.aristotlecircle.com/page/1-to-1-in-home-tutoring

http://study-guide-services-review.toptenreviews.com/what-is-peer-to-peer-tutoring.html

http://www.azcentral.com/news/arizona/articles/20130426education-nation-peer-tutoring-gets-high-tech-makeover.html

http://jobs.aol.com/videos/job-search/rayku-p2p-online-tutoring-program-startup-presentation/517175995/

Peer reviewed (please consider LRS online dbase to retrieve):
Westera, W., De Bakker, G., & Wagemans, L. (2009). Self-arrangement of fleeting student pairs: a Web 2.0 approach for peer tutoring. Interactive Learning Environments, 17(4), 341-349. doi:10.1080/10494820903195249

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http://ascilite.org.au/ajet/ajet26/mcloughlin.html
http://www.sciencedirect.com/science/article/pii/S036013150600090X

http://www.sciencedirect.com/science/article/pii/S0740818807000448

http://www.sciencedirect.com/science/article/pii/S8755461507000734

http://www.tandfonline.com/doi/abs/10.1080/02602930410001689144#.U1J_MvldWSo

Interesting conference proceedings:
Gaofeng, R., & Yeyu, L. (2007). An Online Peer Assisted Learning Community Model and its Application in ZJNU.Online Submission,

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A model to consider, if you have a higher ed instution in the vicinity and replace freshman students with K12 ones. I like how the authors further classified the tutors into 3 categories:

De Smet, M., Van Keer, H., & Valcke, M. (2008). Blending asynchronous discussion groups and peer tutoring in higher education: An exploratory study of online peer tutoring behaviour. Computers & Education, 50207-223. doi:10.1016/j.compedu.2006.05.001

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This is the foundation, which the startup companies from Sillicon Valley are using to make money:
Hsiao, Y. P., Brouns, F., Kester, L., & Sloep, P. (2013). Cognitive load and knowledge sharing in Learning Networks. Interactive Learning Environments, 21(1), 89-100. doi:10.1080/10494820.2010.548068

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this is old, but you can take the concepts and apply them right toward your research of using CAI
Dewey, D. P., & Cannon, A. E. (2006). Supporting technology instruction through peer tutoring, discussion boards and electronic journals. IALLT Journal Of Language Learning Technologies, 38(2), 17.

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this one goes towad
Mengping, T. (2014). Mathematics Synchronous Peer Tutoring System for Students with Learning Disabilities.Journal Of Educational Technology & Society, 17(1), 115-127.

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Tsuei, M. (2012). Using Synchronous Peer Tutoring System to Promote Elementary Students’ Learning in Mathematics. Computers & Education, 58(4), 1171-1182.

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