I have a little pocket pouch of things I might need, knives float separate because I use them a lot. Have pen, carpenter pencil, marker, different tools for different jobs. Have a little tool set, weighs a few ounces has about 10 different bits. little notepad for writing things down. Usb flash drive, 4gb. A little prybar (knives aren't for prying things) and a penlight. all this fits into any cargo pocket on khakis.
Left pocket has a knife, has been for a long time a crkt m21, 3". Simple color, nothing fancy, flipper for speed, sharpened really nice. It's what I use for detail work, envelopes, fingernail cleaning.
In my right pocket I carry things like. Frosts mora, messed with the sheath some so it hangs off the belt into the pocket. 4" of fixed blade simplicity. Ti-lite for a long time, was hooked on the pocket catch. Now for folders I have spyderco byrds, cheap, reliable, not scary, and with a little zip-tie/ rubber band you can give them a pocket catch. Or.... a saw, and some file work.
And since I got it now.... A razel. 3" ringed crkt. The kydex sheath isn't my favorite, would like a leather one. but this is a fun knife. and far more interesting than scary.
Also, the no carrying a knife policies... is just stupid, in school you have boxes full of pointy weapons, heavy bludgeoning objects. But you can't carry a tool.
I got questioned in school once, because I had an RC car battery... it said "rechargeable 7.2 volt" on it real big.... had to explain what it was, because it was shiny and black, and people were scared of it. People are scared of everything.