The father describes his son as energetic, curious, and enthusiastic about learning new things based on how excited he gets about activities at kindergarten. Kindergarten has affected his son positively by helping him learn important social and academic skills through interacting with other children and teachers, and doing activities that challenge and engage him. The purpose of the letter is to share with the kindergarten teacher how much the father appreciates her and what she does to nurture his son's growth and learning.