What are considered to be good writing ECs? Interning at a major magazine? Or just getting published by one? Winning some form of Scholastic award on the national level? and is the regional level impressive too? Do school awards mean anything? Thanks for the help.
The best writing EC is to write every day. And read the authors you love analytically - to understand how they make it work. Try to get your work published - even getting those rejection letters is part of the experience. (I can see the college essay already.) Join a writers group. Take writing classes to hone your skills. Share your work with your English teacher to get feedback - and perhaps to establish a relationship with someone who also loves writing and has reading suggestions for a future writer. Work on the student newspaper or, even better, literary mag - but keep writing. If you can get a magazine or publishing internship, you’ll learn something there too - but keep writing.
Do school awards mean anything? Yes, it means there is a teacher out there who will write you a glowing letter of recommendation about your writing skills. And sure other awards are nice - external validation is always nice and schools like to see it. But getting that validation or not doesn’t change whether you are a writer.
Have you read Bird by Bird by Annie Lamott? A classic. Check it out.
As far as Scholastic goes: regional awards aren’t that impressive. Many people who enter will rack up several of them over their middle school / high school years. I ended up with I think four golds and more silvers from sophomore through senior year. Honorable mentions are even less so; I laugh when I see those included on an awards list.
@bodangles Do you think a Scholastic Gold Key is considered an award with at least some weight then? I have three of these (from my sophomore and junior years) but no national medals, sadly 
Creative writing club.
Writing contests.
Writing on your own!
Yes those are good awards, ignore the detractors. Any activity is good, it doesn’t have to just be about writing. Imagine magazine publishes articles by students on subjects they are involved in too. Check the website.
My daughter created a literature club, she learned leadership in this position. Interviewed and reviewed candidates resume for officers position. One student who took over this club, got accepted to Brown.
She also frequented fan fiction site and wrote maybe a book, not published. She had to do lots of research for historical fiction, which is what she was interested in. She wrote lots of poet rise and teacher often liked her poem and read them in class. But none of this could be captured as ECS except in one essay to Stanford and president of her club. This was a whole back, not recently.
National medal from the Scholastic Art and Writing Awards, pretty much anything from Youngarts, Foyle Young Poets if you’re a poet, a bunch of other poetry contests (Princeton University off the top of my head), publishing credits in literary magazines, founder of your own (successful) litmag.
@shadyconcepts Some, but no more than any other small regional art festival, in my opinion. Too many keys given out to mean much. The website says more than 68,000 works were recognized at the regional level.
@bodangles 17,000 Gold Keys out of 300,000 entries total. That’s 0.5%! @shadyconcepts absolutely should be proud of it. It will carry weight on an app. A National Medal is preferable of course, but even being considered for National is a huge thing. My friend received nine Gold Keys but never a National Medal. This is only part of it, but she’s at Yale now.
@TheWriter9
Probably some bias on my part – I won several golds and silvers throughout hs but only one national medal.
Still, I’d say (even now, a year after the thread’s creation) that the fact that OP had three means a) OP is a pretty decent writer but also b) they’re not impossible to come by.
@TheWriter9, Actually 17,000/300,000 is roughly 5%, not .5%. Still a good award I think but not at the level of selectivity you said.