With an X-Acto knife, cut the bird feeder's opening in the center of one side of the carton for your child. Let him paint the outside of the carton in the color of his choice.
Break sticks (or cut with pruning shears) to about 3" long, and glue along both top sides of the carton to create a roof.
Glue buttons on all sides in flower configurations. Punch a hole 1/2" below opening and insert a 6" to 7" stick for the perch; glue the end to inside back of carton.
Fill your colorful feeder with birdseed and place it outside for the birds to enjoy.