At my school, when I went through it was about $15 and you got a little booklet with information on the chapters. Now (6 years later) it's about $35, you get a t-shirt and a booklet. The money goes to pay for the printing of the t-shirts and booklets, for the reserving of the rooms in the Student Union, and the zillions of copies of stuff that Panhellenic has to give out.
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