schools (not 'centres')

In Spanish we may use the word 'centros' to refer to schools in a general way, or to incorporate both primary and secondary schools.

In English, however, you never use the word 'centres'. You always talk about 'schools', because it already refers to all types of schools.

If you mean to sound really formal, you may use the legal term "educational establishments". But this should only be used in formal contexts (otherwise, it sounds too artificial). "Schools" is neutral and suitable enough for every context.