Got this in mid-January.  My nine year-old is filling this out so to be ready by Mother's Day.  I allow a maximum of two entries per day (he's not doing it every day since he's after-school time is packed and I'm usually next to him when he does fill it out), though this may change if Mother's Day come up quicker than progress on filling entries will allow completion.  I insist that he be very specific for each entry, forcing him to rethink what he will write (and he's doing everything in pencil, too.)  His entries are often very surprising and/or very sweet.