*This was my first time teaching the subjunctive, so I was a bit nervous.  Following my supervising teacher's advice, I made a transparency for the students, to break down how the subjunctive is formed for the irregular verbs, and just to give them some helpful hints.  What you see below is the transparency, with spaces to fill in, so they can actually see me, or a volunteer from the class, form the verb.

Introducción a los verbos irregluares en el Subjuntivo:

Los verbos que tienen una raíz irregular en la primera persona (yo), también son irregulares en el subjuntivo:

dar = doy - terminación = D + 'er' = DE, DES, DE, DEMOS, DEIS, DEN