QUALCHE (a certain amount of, a few, any)
This indefinite adjective refers to more than one thing, but still a limited number of things or people.

It is always followed by a singular noun.

G: Hai qualche progetto per il futuro? –> Do you have any future plans?

R: Sì, ho alcuni progetti interessanti! –> Yes, I have some interesting plans!

G: I tuoi amici mi hanno sempre detto che hai dei progetti interessanti… –> Your friends have always told me that you have some interesting plans…

As you can see from the example, you can also use DEI/DEGLI/DELLE or ALCUNI/ALCUNE with the same meaning of QUALCHE.

Anyway, unlike “qualche”, “DEI” and “ALCUNI” are always followed by plural nouns and they change depending on the gender.

Here some examples:

Qualche libro
Dei libri } some books
Alcuni libri

Oppure:

Qualche albero
Degli alberi } some trees
Alcuni alberi