We dont really have tough pc's (we have dell and hp mainly) but previously in the past we had the problem of vandalism - when I first started one suite had wooden covers glued to the front on the case because some kids had smashed them all...
anyway the approach we took was caging the pc's under desks, some vertical others horizontal. TBH the cages aren't that well designed for people like us who may need to open them up etc, but they protect really well and out of about 200 pc's now cages not are vandalized at all. We had the cages custom made by Walton Designs Limited, Drawing boards, drawing desks, graphics, turnover drawing desk, art, art table, rack and pinion, desks, school furniture, school desks, stackable furniture, multimedia workbenches, low voltage power trunking, pect, pneumatics,
They also desk mounted the monitors which dont protect but make more space and looks neater. As far as keyboards and mice, i found the standard dell stuff fairly tough.