Hi as you need boys and girls to do a voice recording in spanish, i am the right person to do it, i live in colombia and we speak a very clear spanish hear, i have a great microphone to do recordings and also i have audacity (recording program) like that it will have a great quality, i also work with my students they are incredible for this kind of jobs.
My question for you is if you need separate tracks for each exercise or if you need everything in one track ?