According to the DoE calendar, kindergarten has a full day tomorrow, Friday. Suggest you double check with your particular school, but mine confirmed that there's no half-day for K tomorrow.
http://schools.nyc.gov/NR/rdonlyres/CDC0CEFF-CDAE-4941-8448-53D0E9B59F2B/0/20122013SchoolYearCalendar_FinalDraft_3912rev.pdf