They are currently closed to general submissions, but they do have something called the Young Author Challenge, running every year.
Submission deadline for 2017 is May 1 (to be published in October), and here's what the page I linked says about the requirements:
- · seeking stories between 2,000 – 10,000 words
· main characters should be 14 – 21 years old and can be gay, lesbian, bisexual, transgender, or anywhere else on the LGBTQ+ spectrum, including still in the process of working out their sexual/gender identity
· the story should portray positive LGBTQ+ characters who grow or change for the better in some way
· authors need to be between the ages of 14 – 21 (for those under 17, a parent or a legal guardian will have to sign the contract if they accept the story)
This is a paid opportunity (flat pay based on length), each submission is reviewed either way, and copyright remains with the authors.
Disclaimer: I am in no way associated with HarmonyInk. I just thought about submitting to them at one point before they closed for general submissions, and now I came across them again and realised this challenge could be a great thing for those of you lucky enough to not have just turned 22 and thus stopped being young enough

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