Student Web Surfing

This is the first time I’ve asked a question on here. Basically, the college I work at needs to track the viewing history of 50+ lab computers. The catch is that it must be free (IT is seen as a liability here, because we don’t bring in any money). We have a squid proxy that all of the labs go through but only two of our IT know it’s operation. So… we need a simple to read this ip looked at these sites. Thanks!