Shaykh Abdul Azeez ibn Baaz rahimahullaah was asked in his Majmoo` Fataawaa vol. 14, page 297:
Q: Is it permissible to build a mosque, and to build a school from the zakat (obligatory charity) money?
A: That is not permissible; because the aforementioned action (i.e. building a mosque or school) is not something included in the eight categories that zakat (obligatory charity) is to be paid to.