Two students are suing the University of Maine and the state’s public university system, saying they were entitled to a partial tuition refund last semester when the coronavirus forced campus closures in March, leading to the remainder of the semester being entirely online. The lawsuit from Hunter Stewart and Nehemiah Brown is among more than 100 that university students across the country have filed, claiming that educational institutions failed to provide the services they charged for during the pandemic and owe their students refunded tuition. In the lawsuit they filed Thursday, for which they are seeking class-action status, Stewart and Brown say that all 21,000 University of Maine System undergraduate students are entitled to a prorated refund of the tuition and other mandatory fees that they paid their universities last semester.