How does the rest of this verse go: Thirty days hath September, April, June and November; All the rest have thirty-one, excepting February...?

Thirty days hath September,
April, June, and November;
All the rest have thirty-one
Excepting February alone:
Which hath but twenty-eight, in fine,
Till Leap Year gives it twenty-nine.

http://www.leapzine.com/30Days.htm

This site hath 20 versions of this rhyme.

...Excepting February
which has 28 days clear
And 29 each leap year.

If you cannot remember this, another way of knowing is to use your knuckles. If you use the knuckle of your lefthand little finger as January and the gap between that and the next finger as February and so on. This makes the knuckles as Jan, Mar, May, July. Place your two index fingers together and the knuckle of the index finger of your right hand becomes August. September becomes the next gap and October the next knuckle and so on. All the knuckles then have 31 days. Sounds daft but I was taught as a kid and I have used it ever since.

I always use the knuckle method.

I remember the last two lines of the poem as:

Except in a leap year, once in four,
when February has one day more.

I have always known the rhyme similarly to Val:

Thirty days hath September,
April, June, and November.
All the rest have thirty one
Excepting February alone,
Which hath twenty eight days clear,
And twenty nine in each leap year.

Thirty days hath September,
April, June and a speed offender.

Burma Shave