The word hoch (pl. hoši) is a bit archaic and it is not so commonly used by people as before (for example 100 years ago). But you can still find it in literature. So it's just good to know that this word exists.
"hoši" (singular "hoch") used in all areas but most frequently used synonyms "chlapec/kluk" exceptionally "jinoch".
I'm not sure if it's correct to say "The boys are strange," too. Does the Czech sentence imply that boys, in general, are strange? Or could someone say this sentence to refer to a particular group of boys in the vicinity, calling them strange, without the statement offering commentary on boys elsewhere?
I do think the Czech sentence implies that all boys are strange and therefore, "The boys are strange." should be marked as incorrect. In order to refer to a particular group of them, you'd have to include a pronoun, like "Ti/Tito/Tamti hoši...", etc. Also keep in mind, that "hoši" is just one of the possible translations (and IMO not the most frequently used - I'd suggest "chlapci" or "kluci" instead).
The sentence certainly does imply that boys in general are strange. I am native Slovak speaker and the Slovak version of this would be Chalani sú zvláštni. Given the similarity of the languages, I can directly feel what the sentence implies, as I am passively fluent in Czech.
How is “zvláštní” pronounced? It seems the whole cluster at the end is softened (stn → šťň).