What is this case about?
This case is about two middle school students who promoted being vegan
and began campaigning on the school grounds. The school suspended the students who were doing these campaigns. As a response, the student's parents brought this to court on the student's behalf by saying that they have the right to express their ideas and opinions, as said by the first amendment.
How is this case similar to the Tinker v. Des Moines case?
'Tinker v. Des Moines Independent Community School District, 393 U.S. 503 (1969), was a landmark decision by the United States Supreme Court that defined First Amendment rights of students in U.S. public schools.'
as said by Wikipedia. This relates as the school suspended the students for expressing their feelings and thoughts and also their right to petition.
Which type of expression listed in the First Amendment relates to this case?
The First Amendment guarantees freedoms concerning religion, expression, assembly, and the right to petition. So this relates to them expressing their feelings and doing petitions/campaigns.