I did these first with my kids and students in First grade. At that point we only had newsprint and crayons, but when I found art tissue and tissue paper circles the fish grew real scales. Here is a step by step for you to make your own.
First of all, I use SPECTRA art tissue for the fish bodies and good quality circles. There are some tissue circles offered by discount houses that aren't any good at all and the colors are not bright.
The ones I prefer to use are from The TEACHING STORE: http://www.theteachingstore.com/5_tissue_circles_primary_c-p-155463.html#.UAVXdY6zcwI
I posted the link since it was too long for Blogger html. What I ordered is: 20" Art tissue paper in bright colors. 5" Art tissue circles in primary colors.
Here is step one: Easy. Lay out a double sheet of tissue. It can be as large or small as you like, but I suggest at least 18 inches wide or the circles will be too large for the scales.
Just be sure you have two sheets or one sheet folded over.
Next draw a fish shape on the paper. Any shape will do as long as it resembles a fish *:)
Cut the two layers out and begin to use an adhesive tape applicator to join only the top and bottom layers along the edge. Do not close in the mouth or the tail.
Once you have only the top edge and the bottom edge taped, then put the two layers together.
Remember to leave the mouth end and the tail end open so you can stuff the fish later.
Now you can use the same adhesive applicator to make glue strips up and down the fish from the tail end to the mouth end. Only do a few lines at a time, because this can dry out as you work.
Continue to apply glue lines and circles. As you overlap the circles, scales will appear.
Continue this until you have covered the entire fish. I added a big eye that I made with circle sticker paper. It is easy to stick on once the fish is covered. Do the same to both sides, remembering to keep the mouth and tail open so you can stuff the fish.
When both sides are finished you may want to add some long strips of paper to the tail end. Then stuff the fish with old newspaper or other scraps of light weight paper that you would have recycled. Even plastic bags from the grocery will work. But it needs to be lightweight.
Now, once the fish is stuffed you may want to close up the ends with staples or glue, but it isn't really needed. Sometimes I put a string in the fish's mouth and attach a stick. That way a child can swing his fish around like a kite, or pretend to be fishing.
Enjoy your flying fish!
PS.... as an added option :
You can leave all the stuffing OUT, and leave the mouth and tail ends open. Then use a strip of oaktag or heavy paper to make a ring all around the inside the mouth. Attach a string and stick and fly the fish around just like a kite on a stick.