Hi,my friends. I've met a same problem with you. But in that time, I was scared to tell my parents about it. Finally, because of I didn't say anything to my parents, it has been delayed for a long time. So, you could found a right time to tell your mom, your eyes don't feel well and want to check it. Don't be afraid of your mom will blame you. In a word, there is no parents who don't love their children.
That is simple. You get near-sighted and your mopia goes against your studying. This is a bad situation. And my approach is just to tell your mother. To tell her what you are really thinking of. Being near-sighted is not to be shamed of. Most of us wear prescription eyeglasses. If being brave, you finally figure out that it is not big deal. Just say it to her!
Don't worry for that. All parents love their children, so don't be afraid to tell them the truth. When you mention this, don't affirm directly that you have been nearsighted. You just say you have problem in seeing the blackboard. Your Mom will think about it and take you to have your eyes examined. She will listen to the doctor. The doctor knows what is good for you and he may prescribe myopia eyeglasses for you if necessary.
I think you should tell your mom as soon as possible because your vision problem would be worse if your eyes is always in a uncomfortable condition to see things. Getting a pair of glasses will help you correct your vision problem and a pair of good prescription glasses won't make your myopia worse. Actually I think there is nothing more important than daughter's wellbeing for your mom, surely she won't blame you for that.
There is no shame in needing glasses, A lot of people need glasses, you make it sound like it's a bad thing! Just ... tell her ... I think you're making it a bigger deal than it really is, because it will do nothing but help you in the long run, and save you embarrassment.
I don't really see why it's such a big deal.
Ok, it seems that you are very worried about your eye health. That is not difficult. You could just try to describe the situation to your mom, and maybe ask her to take you to do an eye exam to see if you are ok with your vision. That would set your mom's mind at ease, and you really need to make good use of your eyes, provided that the situation is not very serious. Just take care of your eyes and take breaks when you are tired.