Single line bird
If you want to make kites with kids this is a good one to start with. Make a template out of cardbord, cut the ( plastic) sails beforehand and let the children paint it with permanent markers.
The construction is very simple and similar to the Dr. Deleto Eddy:
The frame can be made out of dowel: 1/4" ( 6 mm) will do fine for a 3 ' span,
It needs a dihedral connector and it has no bridle: just tie the flying line to the center connector and it flies.
You can also attach colorful streamers to the wingtips or tail
The alternative for making a dehedral connector is bowing a full length horizontal spar and tying that to the vertical spine; the depth of the bow should be approx. 15 % of the span.
I mentioned a plastic sail, but it can also be made of ( hotcut ) ripstop, tyvek or cotton fabric.