What should I pack for Las Vegas?

Casual light clothes (jeans, shirts - one long-sleeve shirt for sure - and comfortable shoes) and one set of more elegant clothes (still I would suggest comfortable shoes.). Swimwear for the pool and, if you plan to use their cardio room, which is included in the resort fee, you'll need exercising clothes. Bring one jacket in case it gets chilly, but that's about it.

Las Vegas winters are short. It's starting to warm up now and by March it should be in the 80's or so. March is a weird month, though, because it could go higher or lower. By June it will be in the 90's and mid March might have some days like this. There is really no way of telling the weather this early. Wait until a week until your trip and then check the weather.

This is a very casual city so mostly shorts or jeans is fine unless you are going to a fancy restaurant. There are no dress codes for shows like restaurant have so anything will be fine, but it does tend to get chilly in most theaters.

Definitely pack a swimsuit because you're under age so you'll be spending lots of time at the pool. Your favorite pair of jeans and a few cute tops. Depending on which show, something dressy or dressy casual. And a light jacket or cardigan for the nights, it gets chilly. And the most important thing of all the most comfortable pair of shoes you have or can borrow because you will be walking your butt off. The casinos seem close but are not. Have fun I love Vegas hope you will too.

Chap Stick because the desert air will suck the moisture out of you, and earplugs. At least 30 db rated earplugs. Mirage has small rooms and thin walls between them. You'll like the property though, it's Steve Wynn's first effort and is very nice.

Las Vegas has no real dress code. Bring one "nice" outfit for the show, and what ever you would wear for Spring where you currently live.

Well being that you are underage and won't be able to get into most places i'd stick with swimsuits for the pool / hot tub area, jeans, cute tops, shorts.

Something to entertain yourself. book, laptop or e reader.

wear comfortable clothing and a nice cocktail outfit.