I made this as a graduation present for one of my really good friends (we're lame and sentimental that way). It is simple enough for younger kids, though.
Step 1: What You Will Need
Egg Carton; Scissors; Ribbon; Beads; Hole punch; Something to use to poke holes (I used a cake tester); Glue (preferably stick); Paint, markers, construction paper, etc
Step 2: Poke Holes in the Carton
Because of space and time limitations I only poked 6 holes for pictures. But you can poke as many as you want. If you can see in the picture I poked a hole in every other one in a zig-zag pattern. This is where I used my cake tester to poke a hole in the bottom of each crate.
In addition, poke a hole all the way through the middle of the carton so you can pull a string or ribbon through.
Tie your string of ribbon to the beads. I suggest using a square knot. It's really simple and just as reliable. (For those of you who don't know how to tie a square knot it's: right over left then left over right. It can be done the opposite way if needed).
Once you've done this you can pull one of your strings through the bottom of the carton. Do this also for the rest of the crates but pull them through the top just like in the picture.
Step 4: Decorate
If you'd like to decorate the inside of the lid, cut off the two w/e they are to make it flat then glue in pictures or draw or paint, etc. You can do the same to the top of the lid. I did the inside of the lid as a little inside joke between me and my friend.
Step 5: Add Your Pictures
Make your strings whatever length you want and then tie your pics to them.