I was tasked with creating a mandatory fun day for my Platoon, any Ideas to impress my leadership and help boost morale of my battles?

Don't worry about impressing you leadership. Worry about making it fun(ny). Come up with events that will make people laugh.

I recommend:
_Bull in the Ring
_Sumo Wrestling
_Basketball wearing swim fins and boxing gloves, squad vs squad
_Combat soccer (30 people per side, 11 balls on the field, everyone has a sleeping bag in a in a poncho liner to use "pillow fight" style) first side to get 6 balls in the goal (and keep them there) wins.
_Dizzy Izzy
_Surgical tubing Catapult/slingshot water balloon fights

Your goal is to create wild, weird, funny games. If the troops are talking about the games at the club a month later, you knocked it out of the park

https://www.youtube.com/watch?v=R_OIbZshvn0

JBLM has a paintball range that's good for a fun day. Skeet shooting and range time are fun as well. You could also do a day of boating on American lake, hike at Rainier, bowling, driving range, golfing, or a good old ceramics painting class. Follow any of those up with a platoon barbeque to finish up the day. Look on JBLM MWR for more ideas.

Zonk