In the early 20th century, being invited to dance with the adults was a rite of passage. When Clara is invited to dance with her parents, she transitions from being a child to being a teenager.
Ballets include lots of kinds of dances. Choreographer Marius Petipa created ballets during the late 19th century that incorporated many national folk dances, meant to provide excitement and opulence to his full length productions. National dances, known as divertissements in ballet, include steps from many of the folk dances unique to a particular country, such as Hungary, Poland, Italy, Spain. Ballet students learn the steps and style of these dances during their training in character class.