This room has always been our jack of all trades. It's on the front side of the house (opposite the living room and our bedrooms) in the part of the home that used to be the enclosed garage. When the remodel of the home took place (not sure when that happened), the garage turned into 2 additional bedrooms - this room, and the one next to it (which is now the family office/TV room).
We started with a blank slate in here....
And during the first few months this kind of became the storage dumping grounds...with intentions of making it the guest bedroom.
Then we cleaned it out and it officially became the guest bedroom...
It stayed like this for about a year when we realized 1.) we hardly ever have overnight guests so the room rarely gets used and 2.) we needed a place for the toys to go and a space where the kids could play indoors on rainy/cold days.
And that's where we are today...a play/school room that also houses my treadmill ;) This room is big enough for me to workout in after the kids are in bed, and I love looking out the window and seeing the front of our yard while I workout. In the day, it's where William has Independent Play Time and where we do "school."
There's still a bit of work we need to do in here (add some closet shelving to allow more storage, anchor the bookshelves to the wall, hang some things we bought from Ikea, and get some fun curtains), but it's functional and fine for now.
The ironic part about removing a guest bedroom from the house has been that we've actually had more guests stay in this room since we've sold the bed and turned it into a playroom :) It still works out well...our guests either bring pack and plays for kids to stay in here, or we blow up an air mattress for them to stay. I like that it has gone from a seldom-used room to a heavily-used room within the two years we've been here.