A uniform curriculum is the basic call for the day. It is in dire need in order to enhance the educational system in most of the countries. The wide range of curriculum should be submerged into one well established curriculum that can be followed widely all over the nation. This will ensure fair competition and can motivate the student to strive to be the best. Saying this, I take my position in agreement with the argument.
.... you display very good writing skills. Firm stand and good introduction!
The difficulty levels each board offers, differs significantly
... should be differ as it refers to levels
For example, some colleges in India prefer students mostly from CBSE board and if a student comes from an ISC curriculum, 5% of his total aggregate is subtracted before taking him into consideration.
....it's better if you mentioned that students experience many inconveniences due to different curriculums ... that is the core reason and this is a fine example for that reason.
Also, if you are preaparing for IELTS or TOEFL, then it is enough you give just one specific reason and one example to support it becaue you need to handle time too.