Dear [Name]:

I am writing this letter to express my gratitude and appreciation for all the support and help that you have given me during my time as your classmate. I wanted to let you know how grateful I am for all of your kindness and generosity.
Your support and assistance have been invaluable to me, especially during challenging times when I struggled to understand difficult concepts or complete assignments. You always made yourself available to lend a helping hand, and I cannot thank you enough for your patience and understanding.
Moreover, I remember that time when I had to miss class due to a family emergency, and you were kind enough to share your class notes with me. It was a great help, and I am immensely grateful for your generosity.
During group projects, you worked tirelessly to ensure that our team was successful, even when it meant staying up late and sacrificing your time. Your dedication and hard work truly made a difference and contributed immensely to our success.
Your kindness, support, and generosity have made a profound impact on my life, and I am grateful for your friendship. I hope that I have the opportunity to repay your kindness and support to you someday.
Thank you again from the bottom of my heart. You have truly made a difference in my life.
Sincerely
[Your Name]