My younger son is a federal police officer. His cousin has a company teaching defensive handling of firearms. Both regularly carry concealed pistols more substantial than the .380 you can fit in the palm of a hand. You would never suspect they are armed, because they take seriously the word concealed.
I still can't carry at school; and, I don't think they will ever allow it. We do now have six LEOs at school rather than one. They are very large men and each pack two Glocks that can be seen.