Anything done with depth and intentionality, is good. A published short story, a completed screenplay, or even a well-developed novel draft signals creative discipline, sustained effort, and original thinking are all which Ivy League schools value. Strengthen it further by submitting to youth writing competitions (Scholastic Art & Writing Awards, for example), getting published in a literary journal, or sharing it through a public platform. Pair it with a clear articulation in your essays of what this project meant to you and what you learned through it.