In HomeSchool Easy Records, weekdays during the school year are considered "school days" unless marked as "no school" days in the school year calendar. This assumption makes it easier for you to track attendance - you don't have to check days as "attended" all the time. The "Days Attended" (for student x) counts all weekdays since the 1st school day (in Basic Setup) (call this "A") through the most recent day with an assignment (for student x) (call this "B"). Then it subtracts any days marked as no-school days in the school calendar and any days marked as absent (for student x). Then it adds in any weekend school days.
For "Days Attended" it doesn't matter how many days in between "A" and "B" actually have assignments or how many minutes are in the assignments. The time recorded in the lessons only counts toward "Days Earned" which appears only on-screen in the School Year Calendar. Days Attended appears on the Report Card and the Progress Report.