It would be useful for teachers to view at a glance their entire class attendance over a period of time. For example, if I looked at my grade 7 class attendance over the past 3 weeks, I can easily notice that a handful of students are away every Wednesday (perhaps for sports) or that a couple of students are always away on Fridays. Having the 'birds eye view' provides easy analysis to trends that are happening in the class.
Our teachers want the ability to view more than just the current day when taking attendance. In FAWEB, they could view the entire week or a custom date range when taking attendance. This helped them see who was absent on prior days right away rather than having to go back one day at a time.
Some of our teachers have asked for this as well. A teacher may be looking for a trend, that could be helpful in understanding poor effort, etc.