Why we love it:
"Running 17 months, from August 2009 through December 2010,
MOM'S has an oversize, vertical grid with five columns across the top (one for each family member) and the days of the month running down the left side. There's plenty of space for everyone's activities, and Mom and Dad can see who's doing what with just a glance,. Includes a drop-down storage pocket, 500 stickers, and write-on, wipe-off magnetic phone list for the fridge."
Since there are 10 in our family, we each share a column (and all but a couple days a year that works just fine!). I write on it with an extra-fine point Sharpie, putting the child's color-coded initial in front of the activity (look out, I'm color-coding again).
Don't have 5 in your family? Use the extra column(s) to record other events like extended family members' birthdays!