Each year, our Diocese conducts an Annual Catholic Appeal. It used to be in May, but for the past few years, it has been held to coincide with Lent, during which we are supposed to make a special effort to give alms.
One new thing the Diocese of Springfield, MA is doing this year is emphasizing the importance of offering one's time in addition to one's treasure and are encouraging volunteering as part of the appeal. Here is a page with some places where one can volunteer one's time in our Diocese: http://www.diospringfield.org/aca/donatetime.html
I think this is a wonderful idea!