I wanted to make M a 4th of July t-shirt skirt, but believe it or not, I couldn't find a blue t-shirt. This twirly skirt turned out to be even easier (no gathering), and almost as cheap. The patriotic fabric was 50% off at Jo-Ann so I only spent about $3, and it took less than half an hour.
To make this easy, easy skirt you need two coordinating fabrics, some 3/4" elastic. The skirt is made from two rectangles. The bottom one is sewn into a tube, so there's no hemming involved. I used 1/2" seam allowances.
First, decide how long you want the skirt. Then decide how "twirly" you want it. The width of the fabric needs to be at least 2 times the child's waist measurement. The wider, the twirlier.
Main fabric: Width = 2-3 times child's waist. Length = desired length of skirt - 2 inches. Maggie's waist is 20" so I used the whole 44" width of the fabric. The finished skirt was 15" long, so 44" x 13"
Coordinating fabric: Same width by 9 inches (Mine was 44" x 9")
Elastic: to fit around child's waist
Sew the coordinating fabric lengthwise into a tube, right sides together. Turn right-side out. The finished tube will be 4" wide.
Fold down 1" of the main fabric along the length, wrong sides together and sew a casing for the elastic. Leave a 1" opening for inserting the elastic.
Sew the sewn side of the coordinating fabric tube to the bottom of the main fabric, right sides together.
Sew up the side/back of the skirt, right sides together.
Insert the elastic into the casing. Adjust to fit, then sew the ends together. Sew closed the opening in the casing.