1. Get an inkpad off fleabay (I can recommend the make "BRILLIANCE" or "VERSAMAGIC" as it wont smudge)
http://cgi.ebay.co.uk/Brilliance-De...photoQQcmdZViewItemQQ_trksidZp1742.m153.l1262
2. Get plain candle from poundy or home bargains that kinda place.
3. Get some white tissue like the kind they wrap clothes in and take your kids prints onto the tissue. Cut the print out close to the edge then add a dot of water to the back just to hold it temporarily in place then wrap a piece of wax paper around the candle over your image.
Heat gently using a heat gun or a hairdryer or hold over a toaster. The candle should just turn shiny then thats hot enough to fuse it on.
If you dont have wax paper you can use greaseproof.
Also to add photos you can securely tape tissue onto regular copier paper and print out as normal and do as above.
If you want more fun then you could get some "Shrink plastic" and take the kids prints, cook them in the oven (destructions on packets) and make keyrings (Cut hole before shrinking lol!)