Most split-week families already have a calendar. The real question is whether it survives a Thursday when one phone is dead, one parent is stuck in a meeting, and the helper needs to see the afternoon. Three setups come up again and again. Each one fails in a different place, so check the failure before you choose.
Local option: New Plan Care gives families in the St. Louis area in-home help so a parent can stay home: companionship, help with bathing and dressing, meals, and overnight care. Call (314) 405-0887.
The three setups
The shared digital calendar. One calendar that every adult and older kid can open on a phone, with the kids' row and Mom's row set in different colors. It is easy to update from the car and easy to share with a helper. It fails when there is no signal, when someone turns off notifications, or when two people edit the same block at once.
The paper master with a photo. One paper calendar on the fridge, with a photo sent to the family group after every change. It shows the whole month at a glance and nobody needs a login. It fails when the photo goes out of date, or when the one person who writes on the paper is out for the day.
The whiteboard plus a backup. A whiteboard by the back door for the current week, with a digital copy kept as the record. It is the fastest to read at seven in the morning and the easiest for kids to check on their own. It fails when the board is not updated and the digital copy drifts away from it.
Check these before you choose
Who can edit, and who can only view? The helper should be able to see the afternoon without being able to change it.
Does each adult get the alert for changes that touch their row, and can each adult turn off the noise that does not?
What happens with no signal in a parking garage or a school gym? Test it on a day when nothing is at stake.
Can you mark a collision in a color that stands out? The lemon marks are where two rows clash, and if the calendar cannot show a clash clearly, it hides the one thing you most need to see.
Can you export or print the month in a few taps? A printed page on the counter still works when the phone is charging at home.
Who is the backup when the main system is down? Name that person and write their name in the same place as the calendar.
Pick one and keep a fallback
Pick the setup that matches the person who will update it most often, not the one that looks best on day one. Keep a second copy somewhere the helper can reach. The method is simple: the kids' row goes over Mom's row, and the collisions get marked in lemon. For the whole approach, the The Kids' Week and Mom's Week page explains how the two rows fit together.