lihat http://en.wikipedia.org/wiki/Dissertation or /Thesis

karena skripsi adalah untuk S1 sedangkan thesis untuk S2, maka saya pilih mini thesis sebagai padanan skripsi.

In the U.S., 'thesis' and 'dissertation' are often used interchangeably at the PhD level, with no difference in meaning. The term 'dissertation' is rarely used at the Master's level; 'thesis' is preferred. Usually neither term is used at the Bachelor's level -- in the U.S. original written research is rarely required to obtain a Bachelor's degree. There is no widespread equivalent to Indonesia's skripsi for the S1. In the rare case when a candidate for the Bachelor's degree has to do such research, the term 'thesis' is used, not 'dissertation'.

One may find 'final projects' at the high school and Bachelor's levels. A final project is less formal than a thesis or dissertation, does not require original work and may not even involve any sort of written product. It could be for instance production of a computer program or a mechanical device (for an engineering class), production of a sculpture or drawing (for an art class), etc. Additionally 'final project' usually refers to a task required to complete a particular high school or college course, not a task (such as the thesis/dissertation) which is required to complete the degree as a whole.

I cannot speak for usage in the U.K. They have an entirely different system with their own terminology ("A-levels", etc.) that leaves me baffled. Nor can I speak for Australia, NZ, etc.

I hope this is helpful...