Hi,

Fisrt of all, I think if you base your teaching in a good introduction for symbolic logics (it is natural language independent, I believe), the remainig Perl subjects will appear simpler even for non-English speakers. May be not so difficult to be a programming teacher with Spanish speaking students, as to be a programming teacher with any students, when you do not dominate the fundamental. About this you must consider I'm brasilian speaking and philosopher...

Although, it may really be uncomfortable to use a computer language not based in the natural mother language, most of all if you learn the computer language latter (and paying attention on translation of reserved words more than to logical meaning or symbolic semantics). This happens for natural languages as well. So, I sugest you take a look in Portugol. This is not Perl nor spanish, but C and brasilian, and you can even ask for the people involved about applications in Perl.