When grouting, it may be important to note that unsanded grout is more prone to leaving holes in your work, caused by air bubbles I believe. Also, unsanded grout is only recommended for use in mosaics where the space between tiles is about 1/16ths of an inch or less, whereas sanded grout can be used in both smaller and larger spaces.
Also I don't recommend this type of work for kids, unless they are dealing with pre-cut, non-sharp tile shapes and have adult supervision at ALL times! But last and certainly not least, have LOADS of fun with your project(s)!
Anyway, it seems that I'm basically done with this project. I will need to Mod Podge the surface to seal it, however. Here is a picture of the type of glue I use. If anyone has any suggestions on anything that may work better (since I seem to lose tiles on occasion...) please feel free to let me know! Thanks a bunch!