Nice one Chris..

I Understood (Hope) the requirement after seeing the query from Chris... Still not able to bring all the rows.. Not able to get the ID's doesn't have any records in Attend table

Updated Query:

Select A.ID, S.TestName,T.Term, T.EndDate,COUNT(A.PeriodNBR)/8 MissingDays

from dbo.TestScores S

join dbo.Attend A

on A.ID = S.ID

join dbo.Terms T

on S.SchoolYR = T.SchoolYR

and S.Term = T.Term

and S.LocID = T.LocID

left join dbo.Terms T1

on S.SchoolYR = T1.SchoolYR

and S.Term = T1.Term+1

and S.LocID = T1.LocID

Where A.DateABS between ISNULL (Dateadd(day,1,T1.EndDate),'2012-06-01') and T.EndDate

group by A.ID,T.Term,S.TestName,T.EndDate