These measures tend to be resource intensive and more intrusive, but they may be appropriate in some circumstances. If an institution employs any form of surveillance, notice of such should be given to the users. Some schools have found that these measures' greatest effect is discouraging use, and therefore are counterproductive. Consider encryption as an option for highly sensitive data. This includes encoding or scrambling the data so that it cannot readily be interpreted by on-lookers.
Various tools are available for schools.
However, a well designed and enforced acceptable use policy might be a more effective and less intrusive means of addressing this issue. Again, there are several strategies and varying levels of involvement that your school may choose to adopt. In addition to those measures, there are recommendations that should be considered for each individual using public information resources. Teach your students to protect their own privacy by not giving out certain types of information. Question how information is being used.