Our club operates primarily during the school year, as we are a school based club.  We are blessed to receive donations from time to time and rather than distribute them willy nilly without regard to the students' interests, we hold a big student members only auction at the end of the year.  Members earn auction money through participation all year long:  meeting attendance, completing a project, giving a presentation, etc., all can earn them auction money.  This encourages participation, makes it fun, and provides a good way to make sure the donated objects go to interested students... if they like it, they bid; if it's not their thing, they pass.