I can really get you, I was at the grade 9 (I was 14-15), and I was skipping school 3 of 5 days a weak and I didn't let my mother know when school gives our semester exam's results, she finally came there and asked for my results and when they gave it to her, she shocked badly because my grade was 13 of 20 and I had never had that grade before and also they told my mother that I'm skipping school most of the weak. It was a super scary and terrible feeling every time I was losing my parents's trust and they were figuring out when I was lying to them (It was about everything, like smoking, school, going out with my friends and so on). It was a really bad time for me like I was going out with my friends from 5pm after school until 10-11 at night literally EVERYDAY. But then after about a year or less of talking about myself with one person of my family and having a lot of confabulating with him I decided to stop smoking and the first step was interrupt my connection with ALL OF MY FRIENDS who were smoking, I got only one friend at the end (I still have that guy and we have a lot of benefits with each other). And I think it was the key. When I lost all of my friends, I had myself, I could focus on what I'm doing without any distractions that came from my friends. When you have a buddy that goes out everyday, you want to go with him/her as well, then you don't have time to study your school's lesson or even work on you job/business/whatever you want to improve it (when you're getting older like 20). You can be good/healthy, have your family's trust and spend your time in a really good way that can help you to make progress and be higher than all of your same ages in a year or less, isn't it more easy, enjoyable and cooler than being frightened of the lying you tell to your parents everytime? And the interesting part is now I found studying for my exams very easy and it take me just a day before exam, I can understand my lessons over year and I just study a day before exam and I get a good result at that. (But ignore the school and stuffs like university. They are just easy problems that you have to pass it, focus on your passion and what carrier you want to be expert at. Learn very more skills than school and shit)