A system for monitoring and regulating computer usage on a local network is disclosed. Computers on a network are configured with a client activity monitoring module that collects activity information including screen captures, keyboard activity, and/or information relating to network communications and sends the collected activity information to a network activity monitor for storage and later retrieval. Each computer on the local network periodically verifies that its client activity monitor module is operable. If a computer fails to send such verification, the system restricts network access by that computer, thus enforcing compliance with the activity monitoring system. The system further provides means for automatically displaying the collected activity information, including through screen savers, automatically changing desktop background images, and pop-up or sidebar windows. The system thus enables review of computer activities for appropriateness by both supervisors or parents as well as by peer users without requiring the reviewer to take affirmative steps to retrieve the activity information.