Sannara
I've had four generations of teens go to Prom Night. For me, it really depends on what event goals I get.
Gen3: Weaver was my first teen sim after I bought the HSY pack. He ran out of time trying to complete all the goals and didn't even get to enjoy himself, lol. He ended up with silver.
Gen4: My twins both earned gold at Prom Night. I wanted my heir to be Prom Royalty but her shy brother won that title instead.
For the Eat food task, I discovered my sim only had to grab a serving without actually finishing it.
Gen5: Three household teens attended and they all earned gold. Two of them were voted Prom Royalty and Prom Jester.
Gen6: My triplets only ended up with Silver, though the brothers won the Prom Royalty and Prom Jester titles. They just couldn't complete the "Take Photo in Photo Booth" task.
My teen even had the photo he took in the photo booth in his inventory, but it didn't count for some reason.
Personally, I think Prom Night has too many tasks to earn Gold. Unless my teens devote the entire time chasing after the event tasks, they only earn Silver.
Plus, the rewards for a gold prom Night aren't that great. It's a gramophone that can only play the Prom song plus, if I remember correctly, a gold trophy. Not sure about the trophy, actually.
Also, my sims have never been able to complete the Take Photo in Photo Booth task because the game doesn't recognize it's been completed.
I love when my sims get voted for Prom titles, but I'm over chasing after the gold.
good luck and happy simming.