enrollment in kindergarten; enrollment in nursery school
entering a park, garden, zoo, etc.
今日は娘の入園式でした。
Today was my daughter's kindergarten enrollment ceremony.
息子は来月から幼稚園に入園します。
My son will be enrolling in kindergarten starting next month.
家族みんなで息子の入園を祝いました。
The whole family celebrated my son's enrollment.