Spring break from DC with toddlers

I'm mentally escaping the current reality of our country by looking for a spring break travel destination. Here are the criteria I'd like to fulfill:

• Beach
• <5 hour nonstop flight from any of the DC airports
• Accommodations with good activities for a 3 year old and a 1 year old
• Hotel room/suite with separate seating area so we have somewhere to be when the kids go to sleep
• Bonus points for moderate thriftiness. I know spring break is expensive because everyone is going at the same time but these flights are wildddddd.

Thanks :)