Here you can find links to research based publications
National Council for the Social Studies and the C3
iNACOL International Association for K-12 online Learning
The downloadable PDF file can be located here Using Online Learning for Credit Recovery
For information on the TOEFL exam see http://www.ets.org/toefl/ibt/about?WT.ac=toeflhome_ibtabout2_121127
http://www.ets.org/toefl/ibt/about/video_library