Are there references? (If there’s anything which sounds copied and pasted have a look at the source they got it from) – if in doubt put it through a plagrism checker, like this free one -http://smallseotools.com/plagiarism-checker/, if it is plagiarised then depending on how much is plagiarised then either “Reject” it or “Request Revisions”
Are there any spelling mistakes?
Is all grammar correct?
Is the article well punctuated?
Does the article make sense?
Is it written in an appropriate style for young people to read? – could people between the age of 12 and 20 understand it?
Is the article written in a way which is engaging for young people?
Is the article written in a consistent style?
Is the article organised into sections?
Read over the author’s description for spelling, grammar, making sense and suitability. – make sure the author has their details in their profile and an author picture!