Instead of the current calendar that has the inconsistent spread over 28, 29, 30, and 31 days—depending on leap year, leap century, or regular year numbers, it'd be dandy to divvy up the 52 weeks differently. How about 13 months of four weeks each, with the leftover one or two days as bonus day(s) for the 13th month of the year? A year has 365 days in a normal year. Using 13 as the divisor, the quotient winds up as 28 (four exact weeks), with one day left over—two if 366-day year. (Par-TAY! Par-TAY!)
With twelve of the thirteen months having exactly 28 days, all the months could start on the normal first day of the week. As everything would be multiples of seven, there could be huge reduction in confusion over non-synchronization between current calendar day numbering and weekly day numbering. Payroll, scheduling, and programming could be greatly simplified, imo. There'd be fewer calendars to have to buy year to year. (An example of 13-month year advocacy site is 13moon.com.)
Just think! No more "September hath 30 days, ...". In my case, I could never get past the September rule comfortably. A newer ditty completely destroyed any possibility of my memorizing it. And it expresses my sentiment: "Thirty days hath September. The rest I don't remember."
Awhile back, I had learned a handy physical helper until repetition facilitated the memorization. With the hand in a fist, I used the finger-knuckle method to note the 31-day months. The path starts with the index-finger knuckle (January), advances to the pinky-knuckle (double tap to accommodate July and August), and returns to the middle-finger knuckle (December), as shown in the illustration. Tap a few times till you get used to the knuckles representing 31-day months. (The valleys represent the not-30-day months.)
Anyway, as the world is unlikely to change the calendar any time soon, the poem, knuckles, and various paper/online calendars can continue to be the mainstay of day/date consultations. In case you're curious how we got to the messy distribution of days and months, wisegeek has explanations.
Excerpt of interest, when the calendar had only 10 months—
The calendar had only ten months, and the number of days in a month were as follows: 31 days in Martius, 30 days in Aprilis, 31 days in Maius, 30 days in Iunius, 31 days in Quintilis, 30 days in Sextilis, 30 days in September, 31 days in October, 30 days in November, and 30 days in December.Note that the first syllables for 7th (Sept), 8th (Oct), 9th (Nov), and 10th (Dec) months are Latin terms for the ordinal positions. Now, we associate the positions of September as the ninth month, October as the tenth month, November as the eleventh month, and December as the twelfth month. More detailed explanation about these months and the others are at 13moon.com's "WHAT'S IN A NAME?" page.
While I'm on the subject of calendars, the names of the days of the week have long histories and also associations across regions in Europe. Tuesday, Wednesday, Thursday, and Friday retain much of their phonetic and name ties to Norse gods. Encyclopedia Mythica's "Origin of the names of the days" has explanations and also other-language information.
If you need to create your own calendar, my other calendar article will help, but only if you don't try to create a 13-month one.