Letter to The Education Department from Maria (Primary 3)

Dear People at Education Department,  I'm having trouble with my homework and would be grateful if you could please help me.

This is my homework sheet.

Why do my books sometimes have a "the" and an "of" either side of  the date (like Sentences 1, 3, 6 and 8)

and sometimes no "the" or "of"?

and why sometimes  an "on" before the date

When  overseas people answer the question "When's your birthday?",  no one replies  "It's on 7th November" or ""It's 7th November". 
Most people reply   "November 7", or "November the 7th" or "the 7th of November" or "on November 7" or "on the 7th of November" or "11/7" or "on 11.7".   Couldn't  we  learn to speak  like overseas people?

My book has "When's....?" ,                                                                                           but my teacher tells us to write "When is....?"

Sentence 5 is another problem.  People usually say "what's today?" or "what day is today?" , not "what's the day today?"
Why should I learn English that's not correct?
Can I also ask: why do I have to learn "correct" English by studying so much "incorrect" English.  That's not the way I learn Chinese or Math....or the way children in English-speaking countries learn English.
Thank you for your kind help, yours sincerely, Maria
p.s. My older brother Simon also has a few problems with his textbooks

He discovered that it's not correct to call a woman "handsome"

and that singing and drawing are not hobbies

and that we drink, not eat, soup

and  "the children" should be "their children"

wikipedia - but no correct re Aust!

[edit] Expressing dates in spoken English

In British English, full dates are usually written and spoken as 7 December 1941 (or 7 December 1941) and pronounced "the seventh of December, nineteen forty-one" (note mandatory usage of "the" and "of"), with the occasional usage of December 7, 1941 ("December the seventh, nineteen forty-one"). In common with continental European usage, however, numerical dates are invariably ordered dd/mm/yyyy.

In the United States, the usual written form is December 7, pronounced "December seventh" or colloquially "December the seventh".

In Australia, Ordinal numerals are not always used when pronouncing dates. For instance, 12/12/09 is sometimes pronounced 12 December 9 and other times 12 December 9.[citation needed

Oxford dicty:

UK:    3(rd) January 1985 - "the third of January nineteen eighty-five" -

USA:   January 3, 1985 - "January 3rd, nineteen eighty-five"

 

British Council  
'My mother's birthday is on 8th April.' 'My brother's birthday is on 2nd June.'