Spain is full of native speakers teaching really young children - many of them have no experience, no qualifications and no real idea what they're doing. Having said that, a few of them seem to have found themselves a real niche - they love it, are managing to wing it and the kids are having a lot of fun. This is the exception. When I lived in Madrid, I shared a flat with a 20-year-old Brit who had come over on a British Council scheme and was thrown into a classroom as the English-teaching assistant to 25 six-year-olds. She came to enjoy it but for the first three months or so, she spent most evenings in tears. She had no idea what she was doing, the school offered little support in the way of any kind of curriculum and she had no experience with young children.
In my opinion, teaching English to children as young as 3-5 takes two things: a real passion for and understanding of children, and at least some experience of teaching English to older age groups.
When I was in Madrid I taught only adults and only one of them was a complete beginner. Honestly, that was stressful enough. I was railroaded into teaching the 8-year-old son of one of my adult students for an hour a week. It lasted a month. I readily admit I was absolutely rubbish at it. I had had no experience with children in either my personal or professional life and I had no idea what to do with this child who was really only interested in kicking his soft football around his room and counting to ten over and over again.
If I were you, I wouldn't do it - or at least I would consider it only if they take out the requirement to teach children so young and any total beginners. Will you have even finished your TEFL when you go (if you go)?
They only positive note I can see in your post is that you speak no Spanish. I am a great believer in the rule that only English should be spoken in lessons. If you do speak the language of the country you're working in, there is a great temptation to go over to that language and just translate what you're saying when they don't understand. However, it is of course, preferable to speak the lingo because you're living there! It's only polite to learn the language and it will (especially in Spain) be vital in order to deal with the bureaucrats.
