Comments by "Classical LP Vault" (@classicallpvault8251) on "How Your Birth Month Impacts Your Success" video.

Same in the Netherlands except that the cutoff is 1st of October - but it's not a hard cutoff. Bright children born in October will usually still transfer to the next grade technically a year in advance and be still 5 rather than a couple of months shy of 7 when they start to read and write. Meanwhile if you're born either in December or in January you'll typically be among the older pupils in the year so there's no real academic difference between being born at the very end or the very start of a year.
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The cutoff for school class placement isn't the calendar year since school years typically run from September to July, and being born in December is actually advantageous as you'll be among the older children of your year. I was born on December 25th and was always in the highest 15% age-wise of anyone in my class, both primary and secondary school, who never doubled a grade, and was the oldest in my class for half of primary school. The age at the start of the school year is typically used as a guide line and the cutoff is typically between September and October. There it's a disadvantage to be born very late in September, and many children born that late actually spend a year longer in nursery school before they begin learning to read and write to make up for the difference, which, ultimately, still makes them the oldest and most mature in their class so ceases to be a disadvantage. They'll simply graduate from scondary school aged almost 19 rather than almost 18 like they would have otherwise had (assuming they go for the equivalent of the British A-levels, e.g. the highest tier of secondary schooling).
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