You need to filter on the join if selecting only specific records in the left join.

I.e.

Select a.*, b.*

From a

left join b on a.id = b.id

and b.date >= '06-01-2011'

where a.name = 'smith'

Another option is to use a CTE to filter the data first for the saturn.shrtgpa table and then left join to the CTE instead.