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Change the “number of days teacher may alter attendance in PowerSchool Teacher or Schoology prior to the current day” to the # of days to include the day for eLearning.
Side note: This option includes weekends. Use a calendar to figure out what this # of days should be. So, if today is Thursday and we need to change last Friday, we’ll need to allow -6- daysIt is dynamic. 
For example:
Today is January 18th. We allow teachers to change January 12th, So we count back from today back to Jan 12th on the calendar and see that it’s 6 days.
If we leave 6 days in this selection, on the next day, Friday January 19th, the dropdown will start from January 13th to today. (eliminiating the 12th)
Note 2: The default for this setting is “Current Date Only” (turning it back off so teachers can’t change attendance in the past).
--NEW UI--
Click on School Management > Attendance > Attendance Preferences.