Take everything you know about school, and toss it out the window.
Spanish schools are a whole new ball game.
I went to Spain thinking that I would just be assisting with speaking. Little did I know that I would be creating entire lesson plans, and leading classes of 30 students. The teacher is in the class, but they have handed me the leadership role.
This is hard. And it was not what I expected at all.
Many times, I have stood in front of the class not knowing what to do. I have learned to go with the flow. I have learned to improvise.
Silence has a different meaning in Spain than in USA. In Spain, silent means a low hum or chatter. I have had to change my perceptions.
The most important thing to remember is to make it fun.
Students don't want another day of class. They want to have fun. And when your students have fun, you are having fun. Because, suddenly, that student in the back of the class who is always quiet is suddenly participating. That is the rewarding part, and it makes you feel like you are making a difference.
I have prepared worksheets, readings comprehensions, various powerpoints...
The most effective lessons involved a simple game of Go Fish, which works asking questions.
Other games that I have had success with are Heads Up (a phone app), Taboo, Jeopardy, word dominoes, and hangman. Students, from 1st eso to 2nd Bachillerato, love hangman!
Another difference with Spanish and American schools is Spanish students know how to compete, and they like to win. Even more than American students. Just picture a Spanish fútbol game and the energy, then put it in a classroom. Remember to keep students calm during all this fun...
So good luck teaching! Make it fun and you will enjoy the days more. It's a cliché, but seeing your students smiling and learning really is so satisfying.