Public pre-K and universal preschool application windows, lotteries and deadlines in the 100 largest cities and all states with programs, eligibility age and income rule changes, Head Start enrollment and funding changes, seat expansions and closures by district, transitional kindergarten and 3K rule changes, tuition and sliding scale changes for public programs, school choice and preschool voucher programs, waitlist and placement result dates and kindergarten registration deadlines and cutoff age changes, with the city, state or program first and the deadline in the title.