All links below are good as of August 18, 2015.  Most links are to print publications, but some sites also accept submissions for an online version of their publication as well. Click around if you like what you see. Find out what kind of writing they like. Do you like to write in that genre, too? Check for any submission deadlines and age or gender requirements to see if you qualify.

Also go to http://www.newpages.com/npguides/young_authors_guide.htmfor links to at least fifty other publications and contests for high school student writing. (Some of that site’s links are dead, but more are good.) Here’s another good list, though with fewer publications: http://www.tellingroom.org/get-published/places-publish.