Here are my own verses for "Green Grow the Rushes-O" -- 
   https://en.wikipedia.org/wiki/Green_Grow_the_Rushes,_O


Singing my newborn son to sleep, I wanted a longer song, and I recalled
my own father singing "Green Grow the Rushes-O".
I only remembered the last few verses, but Wikipedia gave me up through 7.
After that I started making my own (looking to be a bit more science/math-y,
while retaining a bit of mysticism):

Myself, I sing the verses in odd-numbered pairs, to keep the musical-phrase (per couplet) intact.
That is, after singing down from five, on the next verse I sing down from seven.



17 for the sides of Gauss's n-gon,
16 for the two to the two to the two;

15 for the days in the Ides of March,
14 for the nights in a fortnight;

13 for the doughnuts that the baker bakes,
12 for the root of one gross;

11 for the reach of Apollo's feet,
10 for the Arab system;

9 for the wanderers in the plane,
8 for the eight-fold neighbors;

7 for the seven starts in the sky,
6 for the six proud walkers;

5 for the markings on your door,
4 for the gospel makers;

Three, three, the rivals!

Two, two, the lily-white boys,
  dressèd all in green-oh-oh;
  
One is one and all alone,
  and ever more shall be so.



My own interpretation, fwiw:
- eight-fold neighbors: for a square grid on the plane (as in Conway's Game of Life), each cell is adjacent to eight others.
- nine wanderers [greek "planet"] in the [celestial] plane
- I originally sang "the digit system", for base-ten arabic numerals, but switched "the Arab system" (although it actually originated in India)
- Apollo 11 put human feet on the moon
- As a teenager, Gauss proved that a regular 17-gon could be constructed with ruler and compass (w/o actually doing it).
  This was the first advance in ruler-and-compass constructions in a thousand-plus years!



---------- Traditional version (according to Wikipedia)
I'll sing you twelve, Ho
Green grow the rushes, Ho
What are your twelve, Ho?

Twelve for the twelve Apostles
Eleven for the eleven who went to heaven,
Ten for the ten commandments,
Nine for the nine bright shiners,
Eight for the April Rainers,
Seven for the seven stars in the sky,
Six for the six proud walkers,
Five for the symbols at your door,
Four for the Gospel makers,
Three, three, the rivals,
Two, two, the lily-white boys,
Clothèd all in green, Ho Ho
One is one and all alone
And evermore shall be so.