How did they count the days?

[Jomot]

I suspect that school admission register was filled in by a school monitor or pupil teacher who has substituted children's ages for DOBs for some unfathomable reason.

It doesn't seem to be DoB as 13.4.4 wouldn't make sense in 1876, although as mentioned, it has been transcribed as a DoB of 13 Apr 1904.....

[KGarrad]

Reading the column headings, it was Age Last Birthday, and was supposed to be entered as Days, Months, Years.

Whoever filled in the form entered the age as Years, Months, Days. 13 Years, 4 months, 4 days.

Date of Admission is to the left, and entered as Days, Months, Years.

[Maiden Stone]

Reading the column headings, it was Age Last Birthday, and was supposed to be entered as Days, Months, Years.

Whoever filled in the form entered the age as Years, Months, Days. 13 Years, 4 months, 4 days.

Date of Admission is to the left, and entered as Days, Months, Years.

The original printed column heading looks to me like "Date of Birth". "Age last Birthday " was written in ink over it.
There are a few anomalies on my GGF's attestation form. Answer to question married or single was "yes". His religion was wrong as well. He was discharged unfit 18 months later. I wondered if he was a bit deaf from a decade of work in mills (his daughter was) and he misheard some questions.

[Jomot]

Reading the column headings, it was Age Last Birthday, and was supposed to be entered as Days, Months, Years.

Whoever filled in the form entered the age as Years, Months, Days. 13 Years, 4 months, 4 days.

I see what you're saying, but I don't think its that either as a few entries down is a child with the age last birthday of 29 11 3, so if it was years months days, that would be a very old child!  Another is 31 10 16.   

Apart from anything else, most people are X years 0 months & 0 days old on their birthdays 

I think it is possibly meant to be age on admission expressed as days, months & years - in that order - as none of the numbers in the final column exceeds 16, although even 16 seems old for school admission in 1876.

[Redroger]

Before we criticise the US spelling dictionary we should remember that in many cases modern US spellings are spelling that were used in England in the 18th and 19th centuries. (Look at the word Labourer in many 19th century censuses, usually spelt Laborer in 1841 and 1851, less so later on).
There was no standard spelling before Dr. Johnson's dictionary, and standardisation only caught on gradually, with names it was usually what the clergyman or the registrar heard or thought they heard when the event was registered. I knew two brothers, one of whom spelled his surname Jessup, the other Jessop, there was no animosity, but both insisted they were right.