Which is better: to pray in college with my husband or alone, or to delay it until I get home, knowing that it is difficult to find a place to pray?

A woman's prayer in her home is better than her prayer in any other place, even if it is the mosque. Therefore, it is better for her to delay the prayer until she returns home, unless she fears the prayer time will expire. In that case, she must pray at the college, whether with her husband or alone, making sure to pray in a place where no non-mahram men can see her.