The endocrine glands primarily responsible for the changes associated with puberty are the reproductive glands, also known as the gonads, which include the ovaries in females and the testes in males.
During puberty, these glands produce increased levels of sex hormones (estrogen and progesterone in females, testosterone in males) that drive the physical and physiological changes associated with sexual maturation, such as the development of secondary sexual characteristics, growth spurts, and changes in body composition.
While other glands like the thymus, thyroid, and pancreas also play important roles in overall health and development, they are not the primary regulators of the changes specifically associated with puberty.