MT. VERNON — Mt. Vernon Primary Center third graders put on one of three Christmas performances on Wednesday evening in the gym. The students were led by music teacher Janet Sinks and sang “Frosty the Snowman,” “Snow Day,” and several original compositions. The third graders wrote wintry haikus and performed dances and xylophone music set to their minimalist poetry. Primary Center Principal Shannon Marler said Christmas performances began Tuesday and will continue today as well.