The Rubik’s Build It, Solve It kit is for one player.  Although ages 8 and up are recommended, I believe younger children will enjoy playing with the assembled toy.  As we said before, it is great for children and adults that don’t mind trying to figure out how the cube works – it’s great for those that enjoy putting puzzles together. The kit gives an inside look on how the cube works and how it is put together. Plus, you will receive some tips in the instruction manual on how to solve it.
For decorative purposes, a colorant is typically added to the plastic. The pieces of a Rubik's cube are typically black. During production, colored stickers are put on the outside of the cube to denote the color of a side. The plastics that are used during production are supplied to the manufacturer in a pellet form complete with the filler and colorants. These pellets can then be loaded into the molding machines directly. Rubix Building Products
If there are no more edges left on the top layer, then they are probably either inserted in the right place but flipped, or inserted in the wrong place. To get an edge out of somewhere it shouldn't be, just insert one of the yellow edges into that slot. This should get the edge out and on the top layer, ready for you to use the above instructions to insert correctly. Rubix Build