I saw them on Pinterest, which someone had pinned from Etsy. I did mine a little different, but they still turned out great, in my opinion. So, I'll tell you what I did...
I bought 48 boxes of 24 crayons (do the math... LOTS of crayons!!!) and ten 16x20 canvases. I had measured out that it took 57 crayons to cover the long side of a canvas. Using the 24 packs, you actually only get 19 crayons. I take out black, white, grey, brown, and flesh. So, 3 packs of crayons minus the 15 un-useables will do one 20" side of a canvas.
Draw a line or set the canvas flat against something, because it's harder than it looks to get those little puppies straight! Seriously... that was difficult for me. Hot glue your crayons in to place and let it sit so it firms up. This takes like 10 minutes at the most, because it's hot glue and it's not 65 degrees in Missouri.
MELT THE CRAYONS OUTSIDE!!!! This I learned the hard way... I used a heat gun and started melting. Apparently the dye and wax and paper give off fumes and smoke. I wasn't burning or scorching the paper, but smoke filled the house... so MELT THE CRAYONS OUTSIDE!!!!
Prop your canvas up at an angle... play with this until you find the right angle for you... I was at about a 45 degree angle. I found if I held the heat gun fairly close and then applied heat from the middle of the crayon to the tip that the wax would melt at a speed I could control... now... if you sit in one spot too long you'll scorch the paper AND all wax breaks loose and it runs quickly down the canvas and drips off... oh yeah... make sure you have something under it like cardboard or a vinyl tablecloth... You don't want melted crayon on your table or concrete... MESS!
I also learned after 4 canvases (I did 10 total... sigh), that if you just melt each crayon a little to get it started... then second time across go for your drippy look... then let it set up and 3rd time you can fill in close to the crayons and build the drips.
I did not take a picture of the first canvas... it was crooked and a trial run. I forgot to take pictures of the 4 I did with my niece... BUT I have pictures of the 5 I completed last night... Now that I'm done, I think I know what to do if I ever decide to do this again...
So I have a TON of black, white, brown, grey, and flesh crayons left over... I went through 33 boxes of crayons and I have crayons left... lots of them... I'm not sure what I'll do with them, yet... but there are a few things I'd like to try.
I did use some black, white, and greys up with this:
It's for the girl's teacher.