For a one act for 9th graders, I'd consider "Cake for the Queen" which is published by YouthPLAYS. It deals with people not appearing to be what they seem as well as transformation. It is available on the publisher's website (youthplays.com) as well as on Amazon. It's great if you're looking for something that will accommodate a large cast size. Here's a snapshot of the Amazon entry

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Hans Offenfrish
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