To understand how to escape the vicious cycle of low grades, you need to make yourself aware of one thing: only YOU alone can do this! And you need the right mindset to start with.
Growth Mindset vs. Fixed Mindset
A person with a growth mindset is determined to face challenges, accepts setbacks as a natural process on their path to success, learns from criticism and uses the success of others as an inspiration for their own.
The result of a growth mindset is that you will achieve more than someone with a fixed mindset. You will also experience your life more fully and believe that your efforts are a catalyst for change.
A person with a fixed mindset avoids challenges not to experience defeat, if faced with difficulty they give up easily and they ignore helpful negative feedback and feel threatened by the success of others.
The result of a fixed mindset is that you do not believe that your efforts cause change and therefore you remain rather passive in your life.
You Are Intelligent (Enough)
As a student you should never believe that you are not intelligent because it is not true. If you try really hard (and have support) you can achieve anything (at school or university). Do not give up, be patient and persevere.
Do not listen to anyone who gives you the feeling or even worse tells you that you are not intelligent or talented enough. The scientific research has proven that this is simply not true. Everyone is intelligent enough to understand the topics dealt with at school or university.
Students who are struggling academically generally do not fair well with the standardized approaches to teaching that they experience in educational settings. They would have to be given the freedom to learn in a way that suits them. Especially global learners are struggling with the analytical presentation of content in schools and at universities.
Focus on Yourself
It is important to only focus on yourself if you want to improve your grades. Do not compare yourself to others. Do not be intimidate by negative feedback especially if it is unjustified. Work hard on your skills and believe in your success.
However, do not be immune to constructive criticism and use it as a chance to improve and develop your skills.