Are you using these PC’s on a windows server based domain? if so there should be a GPO, (Group Policy Object), setting to set all users IE temp file space max to whatever you want to set it to, 10,20,30 MB or even less if you want.
There a series of settings in the User configurations section of a group policy that you may want to look into modifying. They are located under User configuration -> Administrative Templates -> Windows Components -> Internet Explorer.
Specifically, you might want to turn off offline pages and under this tree mentioned earlier, go to Internet control panel -> Advanced page and set the “Emply Temporary Files folder when browser is closed” to enabled.