Explosive pencils
I know rumours about poisoned sweets being dropped by enemy aircraft during World Wars (actually my grandmother told me once she heard them as a little girl during the German occupation of Poland). But explosive pencils are new to me. Centro per la Raccolta delle Voci e Leggende Contemporanee is asking about them.
OK, let’s drop some goodies on the Italians.
Pencil bombs were real, but were not disguised as pencils. Well, here it was claimed they were:

Another example, now it is not clear whether you could write with them:

It is not hard to find many brief reports on explosive pencils in newspapers all other the world (the earliest one given by Centro is from 30 July 1917), but the following piece is really remarkable, a long report on two French children allegedly mutilated by explosive pencils (including a photo!):

And now let’s look through the Polish press. First, a 1930 report referring back to the Great War:

The story is told in the context of the Black Tom and and Kingsland explosions. It is not exactly clear whether the “workers” were victims or accomplices. Note that if such rumours were really circulating before the Black Tom explosion, they would predate the stories told in Europe.
Then, we have the existence of explosive writing tools confirmed:

The idea was that bank clerks would use them against robbers. (What might have gone wrong?)
Finally, some propaganda told in a Nazi-sponsored newspaper. Of course, you would be ostracised for having anything to do with such a paper, but it’s interesting that this kind of nonsense reached even Poland occupied by Nazi Germans.
