curtains i think i would do sturdy.

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Since it is a play room how about animals?

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A play room needs no curtains. Get a few colorful pillows , a crisp roman shade and some EASY basket toy storage. Hang some colorful art, with colors from the rug......or better yet, HANG the rug, over the sofa. It has no purpose on top of carpet.

I agree with Jan totally

If you're seeking privacy, consider some horizontal blinds or roman shades for the space. Just be sure there are no hanging strings as that poses a strangulation or choking hazard. Depending on budget, a few brightly colored solid pillows from a local department store would add the pops of color you need on the sofa. Don't be afraid of some patterned and solids mixed in shades of aqua, yellow, orange, red- popular colors in kids' spaces today. (I also own Jack and Jill Interiors, a kids' space design firm.) I love the suggestions by @havingfun for the fox pillow series as well. This is very on trend for today's kids' spaces.

Thanks so much everyone! I like the fox pillows too! I'm going to try to hang up the rug Jan- great idea!

I can think of a few reasons to want to darken a playroom: activities with glow in the dark toys, for instance. Simple solid color panels in primary colors would work and can be found for low prices at stores like Target.

Seems like any primary brights would look good w/ what's there so far. I can envision a series of solid color pillows, each in a color of the spectrum, or reflecting the handprints of the rug. I might do something similar w/ curtains: solids in a series of bright solids, rather than all 1 color, hung across that whole wall, rather than just the window.

And perhaps do pillows in indoor/outdoor fabric to stand up to children's hard use.

the curtain idea sounds really pretty! Thank you!

I like Old Gray Mare's suggestions to use the rug to anchor a place space or reading nook rather than by the sofa. It could even be a space where building blocks are used, etc..

Depending on how little your little ones are, you might want to stay away from curtains to avoid climbing/pulling hazards. I agree, move the hand print rug to create a separate, distinct play area in front of the window. I'd love to see a bench there with some throw pillows on it (to coordinate with what you put on the couch) and baskets underneath for blocks and Legos, etc. Or, a playtable and chairs would go nicely there also. Looks like you could also add a narrow bookshelf to the wall alongside the windows with a few puffs, to create a reading corner/nook.

Don't get too carried away with finding the perfect pillows...it's a playroom. They will get stained and soiled. Get an assortment of primary colors from rug, (red, yellow, green, etc.) and make sure they are nice, light fluffy ones for some good pillow fights :)

many of those pillow covers are under $5 and children love them. cute and inexpensive, can't beat that.