Differences with using Bind variables in TOAD,sqlplus and SqlDeveloper
In SQL*Plus and SQL Developer you need a / at the end of a PL/SQL block.

variable pStartDateBegin VARCHAR2(10);
variable pEndDateFinish VARCHAR2(10);

begin
      select '01-01-2000', '30-11-2011'

      into :pStartDateBegin,:pEndDateFinish
        from dual;


end;
/

[...]