Hello, everyone... I need your advice!

I am going to be taking over for a middle school (6th, 7th, and 8th grade) ESL class in a week in Argentina. This will be the beginning of the second semester for the students (their previous teacher was offered a principal's position elsewhere). Despite the fact that this school is in Argentina, the students that I will be instructing come from 40+ countries, so they will not have the same native language.

I am anxious because I only know their ages (11-14), and the fact that they are divided into 3 proficiency levels (beginner, intermediate, and advanced). However, I donīt know how much of a beginner the beginners will be (False beginners? True beginners?), nor the other levels, because I still havenīt been shown the curriculum and the books that the students are using yet, and I can't get a hold of the previous teacher (long story- no fun to be left in the dark like this until the last minute!).

I am eager to begin to work on how I will introduce myself to the classes, and also a paper that I will distribute to the classes outlining my rules, expectations, procedures, etc. However, I donīt know the best way to go about it, because I donīt want to use vocabulary that is too simple or too complicated (perhaps I should create more than one?).

Is there anyone who might have an idea regarding how to create a thorough handout that my students will understand, and/or a good way to introduce myself (especially to the beginner classes?).

Moreover, if anyone has any good ideas for some icebreakers (the classes are 90 min in length), please share!

Thanks for reading!