Second is because Tang Dynasty is the most prosperous and impacts us Chinese so deep and so long. Litteratues in different dynasties afterTang also produced so many excellent poems. Third is because it's an offical literature format in Tang, Tang poem is one of the most way to test one's ability able to be the officer. that made Tang poems recorded in books, so in the long history, so many poems were remembered. read more
Then kids in Mainland China might learn communist era sayings, songs, etc, while Taiwanese kids might learn more Westernized or Japanese things. Interestingly enough my Japanese girlfriend says she also used to study Chinese poems in school in Japan, even though Japanese culture is much more distantly related to Chinese, they still apparently have to learn some of the old poetry. read more
The answer to this lies in the contrasting cultural orientations and experiences of life during the two eras. By most measures, the Tang was the most successful dynasty in Chinese history. read more