This could help point you in correct direction, regardless of the number of accidents

CREATE TABLE #tblDrivers (DriverID Int, AccidentDate date)

INSERT INTO #tblDrivers(DriverID,AccidentDate)

VALUES (1,'03/01/2012'),

(1,'05/06/2015'),

(2,'08/05/2013'),

(3,'12/01/2011'),

(4,'06/22/2005'),

(4,'04/01/2008'),

(4,'11/21/2010')

GO

CREATE TABLE #tblDrivingSchool...

This could help you...

CREATE TABLE #tblDrivers (DriverID Int, AccidentDate date)

INSERT INTO #tblDrivers(DriverID,AccidentDate)

VALUES (1,'03/01/2012'),

(1,'05/06/2015'),

(2,'08/05/2013'),

(3,'12/01/2011'),

(4,'06/22/2005'),

(4,'04/01/2008'),

(4,'11/21/2010')

GO

CREATE TABLE #tblDrivingSchool (DriverID Int, ClassDate date)

INSERT INTO #tblDrivingSchool (DriverID,ClassDate)

values

(1,'03/15/2012'),

(3,'12/18/2011'),

(4,'07/10/2005')...