I guess not to be confused with "barnen äter glas," which is "the children eat glass." got that one wrong...
I also made a mistake here... A little tip for everyone:
"Ice cream" forms: (1) EN GLASS (2) GLASSEN (3) GLASSAR (4) GLASSARNA.
"Glass (e.g. pane of glass)" forms: (1) ETT GLAS (2) GLASET (3) GLAS (4) GLASEN
No, it's ett barn, barnet; barn, barnen
so barnen is only the definite plural.
Because /the/ child means barn/et/. Barnen means the children. (Indefinite plural of "barn" is the same as indef singular, i.e. "barn".)
Glass can be both uncountable (as above) and countable. When countable, it behaves as a regular en-word. Glass, glassen, glassar, glassarna.
Can you say "Barnen äter jordgubbe glass" as in "The children are eating strawberry ice cream"?
It would be "Barnen äter jordgubbsglass" To insert an "s" between the individual parts of a compound word is very common phenomenon in Swedish. You can make up huge compund words with no spaces inbetween if you want to, but you can't always expect to find them in a dictionary. "Jordgubbsglassätning" ("eating of strawberry ice cream") is a good example of such word.