Why can't the English teach their children how to speak???

My all time favorite song. Love it!! The reason I remembered this was because yesterday I was reading something and I came across the word "conceited" and I was like wow!! thats a word I have not heard in a long time. The everyday English that we use is so different than the English we learnt in school. I am not saying that one is good or bad, it hit me that such simple words are not in use..

Well..I guess its okay. I dont want to say "Jolly Good" instead of "cool" or "awesome" :)