D.D.
Since she's not disruptive I'd say to let the school handle it just as they've been doing. 1st grade is a big change because they are expected to do and sit more and play less. Some kids are able to transition more easily than others. She just probably needs a little more time to settle into the routine.
If you want to work with her on finishing tasks in a timely manner then try setting time limits for activities with rewards when done.