Don't go too dark with wall, keep background white or light grey like painted cement wall

I'm not sure how this could be replicated but does the pic capture your vision?

Lots of graffiti inspired wall decals, so you can change it up in a few years.

Maybe some skateboard shelves

actual room lower east side NY

submit for inspiration only

Maybe some streetlight or stoplight lamps

Maybe flor carpet tiles in these kind of patterns or just plain charcoal (like asphalt)

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Maybe some industrial looking lights or one that looks like a graffiti covered snowboard

@mforr Yes! Love street light idea! I have an authentic street sign from the Bronx that I will hang as well. I looked into an actual artist coming in but all quotes were $500 and up!

mforr's suggestions reminded me that Restoration Hardware Baby & Child has some light up letters and signs you may like
http://www.rhbabyandchild.com/catalog/category/products.jsp?categoryId=rhbc_cat337024

Glad you like it, it's a fun room! :)

Here's some more lighting ideas, love the letters sam0705

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If you google there are also lots of NYC subway maps, signs, etc.
http://www.allposters.com/-sp/Subway-Brooklyn-Atlantic-Avenue-Station-Posters_i2039098_.htm?AID=96280778&ProductTarget=52943993263
http://www.allposters.com/-st/Maps-of-New-York-Posters_c80186_.htm

So grey walls?

How about a little"tongue in cheek" humor?

Light grey, otherwise it'll be too dark.

Sam0705, love the subway stops :)

haha and I love those no graffiti signs - and the industrial lights
etsy is a go-to for me for art in my kids' rooms
http://www.etsy.com/listing/114591499/new-york-icons-graffiti-triptych-mixed?ref=sr_gallery_26&ga_search_query=graffiti&ga_view_type=gallery&ga_ship_to=US&ga_search_type=handmade

Maybe some gray shades or solar shades, gray so that the graffiti is the colorful star of the room.

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If you're going to put graffiti, it probably wouldn't matter what the color of the walls would be. I agree, a faux brick ( http://www.flickr.com/photos/avalonstudios/3169470018/) would look nice.

Graffiti wallpaper:

http://www.etsy.com/listing/115217951/graffiti-wallpaper-color-print

Graffiti peel and stick:

http://www.cadlow.co.nz/index.php?route=product/product&product_id=307

Moss Graffiti:

http://www.inspiringcities.org/guerilla-moss-graffiti/

Be a Graffiti Artist:

http://ny-graffiti-artist-for-hire.com/tag/sports-graffiti/

Some bedding and accessories, and this funky idea for furniture. I don't expect you to paint an antique high boy, but a cool idea for some old dresser or unfinished furniture. Probably could cut up one of those removable decals to fit on drawers or doors.

I thought the light grey for majority of wall so the graffiti would pop and the room would get some light reflectivity :)

Anne dee, that might be the best and scariest idea yet :)

But think of all the fun they'll have and they will have left an imprint on the boy's life for quite some time.
It's a very personal thing. But on the flip side the actual painting of the could be a nightmare. Controlled supervision would be required!

Aaaah no I didn't! It would be cheaper than hiring someone! Great idea!! But not happening lol I'll check out some greys and look into the decals. LOVE the cool lighting suggestions too!! This room will be the most fun to decorate!

Other kinds of bedding, not quite so literal and some skateboard decks for display

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Like this idea, chain link fence gate for bulletin board mounted on wall or mounted from ceiling with lights above or coming thru. I guess the ceiling application depends on age of child and whether or not they'd do something to yank it down, lights and all. That's your call, mom :) the first one has sports stuff on it, ignore that

mforr you are on a tear!! GREAT IDEAS!!

I think I should have been a tagger ;)

Are you implying that you are graffiti vandal?
(I had to look up tagger) lol

Yes, please don't tell my kids;)

What happens on Houzz.......stays on Houzz!

You got that right, anne dee

What about getting a huge white canvas dropcloth and letting your son and his friends graffiti it? You can hang it on the wall, bind it as a rug with a black or grey band around it or make it into floor pillows for when his friends visit.

Love the floor pillow ides!! That's great :)