"È stato trovato qualche osso."

Translation: Some bones were found.

[Francis14]

So ossa becomes masculine singular in the plural and takes singular verbs...?

[coriolano77]

Osso is masculine singular, ossa is feminine plural. Qualche means a few or some, but is always followed by the singular. You can say the same thing in this way "sono state trovate alcune ossa".

[Francis14]

Thanks!