A correspondent has reminded me that Easter does not finish with the evening service on Easter Day or the return to school a couple of days later. The Great Feast/Festival of Easter runs from Easter Day to Pentecost. (Keep eating those eggs!). Liturgically we acknowledge this fact by extending our greetings and salutations.
Thus in A New Zealand Prayer Book we find the following:
at the beginning of a daily service (e.g. p. 58)
Open our lips, O Lord
and our mouth shall proclaim your praise.
(In Eastertide: Alleluia.)
at the end of a daily service (e.g. p. 60)
the concluding Amen to the last prayer in Eastertide should be:
A final observation about the Great Feast of Easter ... the 'Alleluia' of Eastertide is not merely a liturgical addition, its a, or should be a heartfelt expression of the joy of the risen Lord alive in ourselves and alive in our church.