Thanks a lot my friend,you helped me quite a lot. Concerning the translation of Magister to "Master",it is because I am Brazilian and in fact the word was "master" in Portuguese so I had to put the translation in english to ask your help!Ulpianus wrote:1 looks right to me (though I would prefer "teacher" to "master" as a basic definition of magister so as not to get muddled with dominus).
2 I'd translate (I think, it's an odd sentiment): The battle had been dangerous/destructive for the boys not the teachers. Literally: the battle not for the teachers but for the boys dangerous had been. What you have is a simple sentence proelium ... perniciosum fuerat and two datives non magistris sed pueris which indicate the people for whom the battle was dangerous.