吴小丽 put it perfectly! If I were to correct, I would only say the first two sentences differently in order to perserve the original meaning: 明天我将结束第一周的汉语课程。这星期我和中国老师聊了天，学了非常多的知识。
I would like to comment on the use of 关于. Although it can be translated to 'about', you can't always translate 'about' to 关于 because the use of 关于 is much narrower. It can only be used to add a complement of a noun, like 关于特殊教育的电影(a movie about special education). Here 'a movie' is the noun and 'about special education' is the complement. Basically, when you use 关于XX, there has to be 的 plus a noun that directly follows it. Some phrasal verbs in English (i.e. 'talk about' and 'know about') can be translated into one word in Mandarin (i.e. 讨论 and 了解). In this case, 关于 is not needed at all!