Teacher warns students not to spoil 'Avengers: Endgame' with fantastic note

This is One Good Thing, a weekly column where we tell you about one of the few nice things that happened this week.The first weekend of Avengers: Endgame is finally upon us, and people are desperate to avoid any spoilers for the highly-anticipated film. 
In a desperate attempt to keep the details of the plot at bay, fans have been blocking certain keywords on social media, avoiding some news sites, and taking other desperate measures. There's even a notable #Don'tSpoilTheEndgame hashtag on