Just get an Icon/aluminum shaft. Everyone is going to reccomend a middle-line stick, but a mid level one would cost $75+. Especially at the 7th grade level, this will be fine. Some of the better players might even be using it.
As for rules, they should teach you most of them. I will review some. You always have to have 3 people on the offensive side, and 4 on the defensive, so make sure to not cross the line, without yelling "middie back!!!". I reccomend not doing this yet, as it is confusing for begginners. Just stay on your side.
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