The Dance Class was exhibited in 1876 at the second Impressionist exhibition. The subject of the work is a dance class conducted by the famous ballet master Jules Perrot. The work is generally thought to be a tribute to the teacher rather than a depiction of an actual class conducted by him. The scene is a careful arrangement of what seems to be a random collection of postures and poses. One ballerina, who is the central focus of the composition, dances while the others mill about around her, presumably waiting their turn. Some adjust their costumes, while others just sit or stand in various postures. The women in the background on the right are the dancers' mothers, who chaperoned their young charges during the rehearsals and were there to either protect the girls from or introduce them to the wealthy male subscribers who visited the dance halls and often watched the rehearsals.

Like most of the dancers in Degas's works, these ballerinas are not performing. Degas has caught them in the unglamorous environs of the practice hall. Just as interesting as the dancer performing a graceful arabesque is the sight of another dancer in the foreground, bunching up her skirts, or the girl in the far background adjusting her choker.

The overall composition is marvelously complex and fluid. One's eyes settle on the music stand in the foreground on the left and travel back in various directions: perhaps to the dancer directly behind the stand, to the girl with the bent head directly behind her, to the ear and bun of the dancer behind both, then up to the dancer between the poster and mirror, and to the ballerina doing an arabesque. Then our eyes may wander across to the seated figures or up the left wall of the room to the dancer leaning against the wall and looking up at the one tugging at the ribbon around her neck.

We may linger on those formal elements that draw us outside the picture's frame: part of a dancer's shoe and tutu on the right, a portion of a cello, a ballerina facing away from the viewer on the left, the cropped ceiling and moldings. We might also pause on details, such as the foreground dancer’s locket, a flower being trod upon behind her, or the scrap of white on the floor behind the dancer in an arabesque.

Formal elements echo one another throughout the composition. The two dark-haired dancers behind the music stand seem like the same person seen in successive movements, while the girl behind them stands back-to-back with a dancer that seems to be her mirror image. The color red appears in the flower in the foreground dancer's hair, in the dance master's shirt, and in the wrap of one of the mothers.

The mirror on the left wall serves a number of compositional functions. The reflection of more dancers continues the rhythmic line of the dancers in the foreground and middlegrounds. The reflection of a window provides the illusion of a city vista, creating spatial depth that would otherwise be on the right side of the room. The vertical division within the mirror's reflection also echoes the lines of the dance master's cane and of the music stand in the foreground, providing visual points of reference.

The artist Mary Cassatt, a good friend of Degas, repeatedly compared this work to that of the great seventeenth-century Dutch painter Vermeer, claiming that Degas's work was superior to his. She was probably referring to the artist's complex articulation of forms and textures, his depiction of light and reflection, and the overall mastery of his handling of paint.