If the institution was serious, they would consider extra editions of the new Liturgy of the Hours effort. For half a century, we’ve had the four volume set, which is luscious. There’s also the Christian Prayer edition. And the “Shorter” version of the latter.
I think Compline for children and parents would be a good way to go. It takes one element of the Divine Office and makes it accessible for families. I could see a one-week cycle for children up to about age ten to twelve-ish. Parent-led and composed for bedtime prayer. It would need to be well-illustrated, something like a picture book. Prayers well-adapted like the Children’s Eucharistic Prayer. Probably some freshly composed material.
Additional supplements to the prayer for the four special seasons, and perhaps other prayers for the various climatic seasons: winter and summer and the ones in between. Of all the Hours, Night Prayer strikes me as potentially the most family-friendly. The outline could be simple:
- Sign of the Cross
- Brief penitential rite (good options would be a simple Lord Have Mercy or the Act of Contrition)
- Psalm (I would include the classics–4, 91, and 134, but also Psalm 121 and especially 131.)
- Reading (which I could see a new Lectionary including readings that mention young people like 1 Samuel 3 and Jeremiah 1)
- Canticle of Simeon
- Closing Prayer
- Antiphon to the Blessed Virgin (options from the Hail Mary to the classic four)