During WWII, various artists from the different cartoon units (such as Looney Tunes, Disney and Walter Lanz) all gave their time to the war effort by working on training films (among other things) meant only to be shown to the soldiers. Because of this, the cartoons were not in color but DID have some colorful content...such as swearing and sex jokes! I can only assume that folks thought that if the young men were old enough to die or kill, they were more than old enough for some bawdy humor.
The Technical Fairy First Class is back and he's giving the soldiers a lecture on camouflage. Most of the examples feature Private Snafu and the lecture is only occasionally funny....and so I would not place this among the better films in the series. For that, try one such as "Booby Traps"....now that is filled with laughs.