Hey bro (I actually am a sis lol
). It does make a lot of sense what you are saying and yes, it does feel a bit guilty not to do the lesson plan. BUT, here is how I stand in this school, so that you (and others) have the complete picture. I have been actually teaching for two years in a school (this is my third year) and a lot more as private tutour of English. Thing is, we are a tiny little school of about 120 alltogether (from Pre-K to highschool) and until last year I only had very very young students (ages ranging between 3-6), with no coursebook to base my teaching on, so you can say that the time I spent on the Internet searching for materials accounts for a hell of a lot more than the time spent on a lesson plan. I will carry on teaching the very young (I am struggling to make the school adopt a coursebook) and as from this year I will take the Juniors as well (6 to 9), with whom I will work from a coursebook. Now, as far as the teaching experience is concerned, the reason for a lesson plan for me is purely based on a need to single out the objectives of a given lesson. Other than that, I have learned that in a class of, say, 16, you might need 16 different teaching approaches.
One very important thing I have learned so far: make the students love you and you are a successful teacher. I must admit the feed-back i got from parents last year was beyond all expectations (they were looking for me to tell me that their kids loved me, which really is a reason to wow! about). Consequently, they were all looking forward for "English time'. Not having coursebook made things very difficult for me, but once having established a routine (now it's song time, now colouring time, now talk time) made it easy. Also, the "carrot technique" works: I would only sharpen their colour pencils if they asked me to in English, Cannot tell you the delight of both the teacher and the students to say and hear say, respectively "Can you sharpen it please?". In any case, always have back-up activities ready. At this age thay love colouring, sticking, cutting, doing things with teir own hands, it's a play/games-based teaching.
Well, so long for now, if you have more questions don't hesitate to ask them, measwhile I am waiting for more answers from the masters in the business.