Americans are faced with a choice: either we open our borders or we turn our backs on the needs of desperate people.
This presents only two options when others exist, like temporary refuge, foreign aid, or international cooperation. The argument would be stronger if it acknowledged these alternatives.
Across the country, we have seen so many cases of teachers openly expressing their political beliefs in the classroom
This generalization might overstate the trend. A more accurate claim would be "many teachers" rather than implying almost all teachers, since some may never express political opinions in class.
The First Amendment guarantees the right of free speech to all Americans.
The argument assumes this is absolute, but it ignores exceptions like workplace rules, hate speech laws, or confidentiality requirements. Not accounting for these weakens the general claim.