GIRLS LIFE seems to have some trouble keeping straight the submissions from minors (which, like many kid magazines, they neither contract for nor pay for) and freelance writers. In fact, I've seen some folks get kind of irate about GIRLS LIFE using material without paying (and, in at least one situation, without a contract) So, apparently you really should mention that you're expecting them to PAY for the work. The way I normally do that when I've dealt with newspapers (another entity prone to forgetting that all writing isn't a present) is to use this as my final closing line of the letter: "Thank you for considering "NAME OF PIECE" for Girl's Life magazine at your normal freelance rates." Which should keep the first reader from filing it with "free stuff." Since I've been reading of actual mix-ups (though at least one of the folks complaing was a young girl and I really don't think GIRLS LIFE pays young minors ever), I might be inclined to put "freelance submission" on the manuscript too...under the spot where you put the word count.