23. Exemptions from or Reductions in Educational Supplementary Fees and Embankment Defense Fees for Enterprises Located in Industrial Cluster Zones.
http://www.federalregister.gov/articles/2009/01/07/E8-31175/...

The term "educational supplementary fees" is excerpted from a report from China. I personally think that the word "educational" is redundant here. In most schools and universities, "supplementary fees" is sufficient for "教辅费".

See http://www.google.com/#sclient=psy&hl=en&source=hp&q="supple...


Course supplementary fees may be charged to students for materials or services associated with particular courses or sections of courses.
http://www.ucalgary.ca/pubs/calendar/current/p-1-9.html

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Note added at 2 hrs (2011-07-22 09:04:15 GMT)
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You may also add the word "materials" in "supplementary materials fees" for "教辅费".

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Note added at 10 hrs (2011-07-22 16:55:57 GMT)
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If you want to specifically refer to the supplementary materials for test or examination preparation (such as TOEFL or GRE preparation materials), you may try "examination preparation materials fees" or "test preparation materials fees".

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Note added at 10 hrs (2011-07-22 17:01:58 GMT)
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Or you also add the word "supplementary" for "examination supplementary preparation materials fees", "test supplementary preparation materials fees", "examination supplementary study materials fees" or "test supplementary study materials fees".

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Note added at 10 hrs (2011-07-22 17:03:13 GMT)
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Should be:

Or you may also add the word "supplementary" for "examination supplementary preparation materials fees", "test supplementary preparation materials fees", "examination supplementary study materials fees" or "test supplementary study materials fees".

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Note added at 10 hrs (2011-07-22 17:07:52 GMT)
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To shorten your term "“supplementary workbooks” that are often exam-oriented", you may try "supplementary examination-oriented materials fees".

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Note added at 10 hrs (2011-07-22 17:32:52 GMT)
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Moreover, there is also a word "cram", which means "to prepare yourself for an examination by learning a lot of information quickly", for example, "test-cramming materials". However, the word "cramming" usually has a negative connotation.