Hi Tammy!
Good call in choosing to visit Walt Disney World in the late spring timeframe. The weather is usually gorgeous and hopefully you'll be smack-dab in between the spring break rush and the early summer vacation crowd.
Since schedules and hours are subject to change, I'd recommend checking the
Theme Park and Water Park Schedule on the Disney Parks website now as you're planning your visit, and maybe once more as your vacation draws nearer. I took a quick peek, and it looks like they already have the schedules for Extra Magic Hours posted for the time you'll be visiting Walt Disney World.
Here's a bonus tip:
If you have a smartphone, make sure you download the My Disney Experience app. It'll be a handy tool for checking out park hours, show times, and even wait times for certain attractions.
I hope that helps. If you should have any further questions, please feel free to send them my way and I'll be happy to help in any way that I can.
I hope you have an awesome vacation!
Best regards,
Derek