There is multiple ways to earn free bitcoins. Quite a few of them are listed here:
http://bittikolikot.com/freebits/I have personally made over $15 just this month alone purely from faucets. Of course it's not going to make you rich but definitely counted as free bitcoins!
$15 in a month is a quite low buddy. faucets are good, but not good for long-term imo. i prefer signature campaign because you can earn more than faucets in a month.