Massachusetts students have a right to free speech at school, but not to be disruptive.1
Example: Devlin wears a t-shirt with a hammer and sickle logo on the front and “Make America Great Again” on the back. Her school’s assistant principal tells her to change the shirt or to cover it because it is “too political.” Devlin tells to him that she has a right to wear it and to express her political views. And she is right.
But students can be disciplined for being absent from school, as long as the school does not treat people differently because of the student’s views or expression and as long as the discipline follows the school’s policies.
Example: Miles is absent for the 11st time of the year, one more than the allowed 10 absences. He was at a protest demanding the city fire his school’s principal. The school suspends him for 30 days. However Oz, who also had 11 unexcused absences (he has been traveling in Mozambique with grandparents) gets only one hour of detention. Miles objects. Upset that he’s being punished because of his views/expression he rightfully asks the school to explain difference in punishment.
In other words, there is no special right to miss school to engage in protests, rallies, or demonstrations.
But many schools have policies of:
Not disciplining students for being absent until the number of absences exceeds a certain number; and/or
Allowing absences for certain reasons, often with permission of a parent and principal.
Before you miss school for a protest, you should check your school’s policies to see if being absent might get you disciplined. Also, try to find out if there is a way to get permission so that the absence won’t count. This way you’ll know if you might get in trouble for missing school for the protest.
The school can’t treat absences for rallies and protests any more harshly than absences for other reasons and can’t punish you more based on what you might be protesting about.
1Massachusetts General Laws c. 71, § 82 https://malegislature.gov/Laws/GeneralLaws/PartI/TitleXII/Chapter71/Section82