Final answer:
Excessive homework can negatively impact students' mental health and overall well-being.
Step-by-step explanation:
A good claim for an argumentative essay on why homework is bad could be that excessive homework can negatively impact students' mental health and overall well-being.
For example, research has shown that high levels of homework can lead to increased stress, anxiety, and sleep deprivation among students.
Additionally, homework can limit students' opportunities for other important activities such as exercise, relaxation, and socializing.