Fun, easy build, some easy soldering required

Step 1: Supplies

You will need:
Old head phones
Duct tape

Tools:
soldering iron
pocket knife(or something to cut and strip wires with)
Electical tape

Step 2: Taking Apart the Head Phones

Take off the fuzzy thing,then snap off the plastic part, so all thats left is the speakers.

Step 3: Wires

Cut the wires about 8in (or more) away from the jack. put some electrican tape wher the two sections split about 3 in from the jack. strip off the black coating about 3in from the ends, the strip the ends of the inside wires about 1-2cm from the ends.

Step 4: Solder and Check

solder the wires to the contacts on the backs of the speakers.
when you are done, plug it in and see if it works.

Step 5: Part Two: the Case

Make a flat slab of duct tape, plca everything on it to make sure you know where it's all going. first tope down the wires, then make a slot for the Mp3.
Finaly tape atound the "speakers".
for the mp3 slot you may want to leave a spot open for the bottons/screen