One schedule both households can see. Events, handoffs, and notes in one place — so nothing depends on remembering a conversation.
Nothing to sign up for. Everything you enter stays in this browser on this device.
How the two of you stay in sync
There is no server and no account, so this copy does not talk to the other household by itself.
When you have made changes, open Settings → Sharing and tap Copy update link. Text or email that link.
When they open it, they get a choice: merge your changes in, or ignore them. Merging keeps both sides' events, notes, and expenses, and honours anything either of you deleted.
Each of you can also add the schedule to your own Google Calendar with the calendar file — no permissions, no sign-in.
Want it to sync by itself instead? That needs a small server. Ask and it can be added.