On the campus of Houston University, students meet in small groups, sit alone at computers and attend virtual meetings.
It appears they are taking precautions against the coronavirus, but the Texas metropolis is still rushing to get its population of about 300,000 university and college students vaccinated as quickly as possible.
"Right now, college students make up a large percentage of super spreaders," said Isaiah Martin, 22, a fourth-year student in political science who is leading a campaign for students to get their shots.
With some 500 new cases a day in April, down from about 2,000 in January, the situation in Houston -- the fourth-largest city in the United States -- is improving, yet it remains worrying.
Where it goes from here will depend in large part on the behavior of students, many of whom are chafing under a year of restrictions and isolation.
But a College Pulse survey in January of 1,000 US students found that only 21 percent were not concerned about vaccine safety.
- Vaccination competition -
At the University of Houston, home to 47,000 students, Martin says his peers still "go out and a lot of time they ignore the guidance from the CDC and other health departments and so they'll go out, they'll party, they'll do things college kids normally do."
After more than a year of the pandemic, words of caution are increasingly difficult to heed.
That is why the city has organized its "Take Your Best Shot" campaign, a competition between universities to see which can get the most of its current and former students vaccinated.
The competition began March 29, the first day the vaccine was available to all adults, after Texas decided it had sufficiently inoculated its at-risk population.
Vaccinating students is deemed so important that Houston Mayor Sylvester Turner came to the University of Houston to kick off the campaign.
- 'Don't even know what I'm missing' -
Rice University, the most prestigious school in the Houston area, is not participating in the challenge. It has, however, set up a vaccination center managed by hospital group St. Luke's Health on its campus in the heart of the city.
On this April day, several dozen students received their first doses, hoping to put an end to online courses and limited social interactions.
"I think online classes have been isolating and we haven't been able to learn as well in our dorm rooms instead of the classroom," said Sarah Sowell, 19, after getting her shot.
First-year students remain the most isolated, having never experienced the highlights of campus life and its close friendships.
"It's hard to make friends when you only see them on a Zoom call, they're only little pictures on a screen," said Lillian Cui, 18, who came from Pennsylvania to study planetary science.
English student Hannah Hoskins, who also came to Rice at the start of the academic year, finds it "strange to hear these really amazing stories about previous years and I think that's a little difficult to have to be like 'Man, I'm missing out,' but I don't even know what I'm missing."
On the other hand, older students struggle with separations they assumed would be temporary but may now be permanent, as friends stay home with families in other states or sometimes abroad until graduation.
"I'll be graduated in May and a lot of my friends left Rice in March (2020) and were not able to return last year because of the coronavirus," said French student Anna Margaret Clyburn.
"Now I fear I won't get a chance to reconnect with (them) for a very long time, if at all," she said, noting that in a few months she will move to San Francisco to start her first job.