One national tutoring agency, Exam Confidence, told the Guardian it charged schools up to £1,400 a day.
Elizabeth Scheibel, the district attorney in the South Hadley case, declined to charge school officials who she said were aware of the bullying because of their "lack of understanding of harassment associated with teen dating relationships".
While public schools do not charge school fees, associated costs like uniforms and supplies such as exercise books, pens and pencils are the responsibility of families.
Common Cents does not charge schools for this service.
Some authorities have reportedly refused to shoulder this burden and are considering charging schools for the legal costs of conversion.
Linden Lab, which created Teen Second Life, charges schools a one-time fee of $700 to buy and own property in its virtual world and a $147.50 monthly use fee.
Exam boards charge schools and individuals for re-marking, with fees ranging from about £40 to £90 a review, depending on the service requested.
Chalkable plans to charge schools $10 per student, of which $5 will be available for purchasing school aids.
WeSchool plans to charge schools and companies an annual license fee for accessing the software as a service.
Since the website only required limited and basic technical options, there was no need to charge schools for using the CAPTT.
