If you like fishy-fishy, as 鱼 sounds like 余 which means "abundance".
Nian Nian You Yu (年年有余) = abundance of money year after year
Here is another simple craft you can do with your children using red packets, a scissors & a stapler...
Fold in one side to make a big corner.
Use a scissors to cut out the shape.
Cut in between the tail until halfway.
Take 1 side of the "tail" & intersect the other side of the "tail" & use the stapler to staple at the intersection.
Tadah...a fish is created...
Here's wishing all of you a Prosperous Chinese New Year! Huat ah!