I love the bubblegum necklaces for kids. I saw quite a few on etsy and tutorials on blogs on how to do it. Toys R' Us does have a huge container of gumballs that I bought. I drilled holes in them with a hand drill. I used the 5/32 bit which was so much larger than I thought I was going to use but I wanted to be able to put the ribbon through it instead of just a string. I taped up the end of the grosgrain ribbon with packing tape and twisted it really tight. That way it would go through the gumballs. I put a knot in between each gumball. I made one below for myself that is white and red with a grey ribbon. I love it.
I did spray paint them with a clear coat of paint. I wasn't sure what would happen when you actually where them next to your skin. I caught one of my daughters having it in your mouth and it did start to crack. I can't imagine it tasting good after the spray paint on it.