When does the year begin?

When the year finishes/ends, you think in about/of the purposes and aims for the next year. We celebrate the New Year very happily and to begin with the battery fully charged (you mean to start fresh?/to begin the year with full energy?) But, for me my, really the year begins in September, there are a lot of things that start in that month. The school, If you want to study (take) a course or learn to dance, the classes start in September. In addition, yet there are a lot of tasks/things that have on to be done during the holidays in August and they people come back to work in September.
I assess (what do you mean by assess ?) my year three times per year. At Christmas, in September and when is during/on my birthday. But, I think the most important moment to start the year is in September, you have to plan all the things  everything. For that reason,now I´m writting down the goals that I would like to achieve next year, in September. The first and main aim is to improve my English. If you have any fun ideas to learn the of how to learn English, tell me!!!