So, after a lot of thinking and engineering in my head, I managed to shorten the sleeves and raise the skirt without cutting any fabric. By adding lace to the sleeves and skirt, the folded extra fabric is totally disguised. I also added a lace "cape collar" to hide any pinning needed to take in the shoulders and bodice. I also made a Colonial side pouf apron to cover the distance between the costume's waist and the little girl's actual waistline. It actually looks pretty good. The mop cap ties the outfit together.
The 3rd Grade classes are doing a Wax Museum. Each student made a poster about the historical figure they were assigned. At the event in the gym, each child will be dressed like their character. They will stand frozen in a pose while the parents walk through viewing the characters and read the posters.
P.S. I actually got to go to the Wax Museum. Lyla looked great as Betsy Ross. It was educational to see all of the students dress up as wax figures of famous people. The students stood frozen standing for a few minutes, then sat frozen for a few minutes. Pretty impressive for third graders to stay in character and quiet for so long!