I'm going to take a quick stab at this since nobody has responded yet. What I am showing you here is not a complete solution but should get you moving in the right direction.

First, msdb.dbo.sp_help_jobactivity should give you a number of columns: the query below runs fine for me on 2008 and 2012.

DECLARE @job_hist TABLE

(session_idint,

job_id varchar(100),

job_name varchar(200),

run_requested_date datetime,

run_requested_source int,

queued_datedatetime,

start_execution_date datetime,

last_executed_step_id int,

last_executed_step_datedatetime,

stop_execution_date datetime,

next_scheduled_run_date datetime,

job_history_id bigint,

[message] varchar(1000),

run_status int,

operator_id_emailedint,

operator_id_netsentint,

operator_id_paged int)

INSERT @job_hist

EXEC msdb.dbo.sp_help_jobactivity

SELECT 'Scheduled' AS Scheduled_or_manual,

PATINDEX('%The Job was invoked by Schedule%',[message]),

*

FROM @job_hist

WHERE PATINDEX('%The Job was invoked by Schedule%',[message])<>0

UNION ALL

SELECT 'Manual',

PATINDEX('%The Job was invoked by user%',[message]),

*

FROM @job_hist

WHERE PATINDEX('%The Job was invoked by user%',[message])<>0

That said, you can also get this information from msdb..sysjobhistory

SELECT 'manual' AS Scheduled_or_manual, *

FROM msdb..sysjobhistory

WHERE step_id=0

AND PATINDEX('%The Job was invoked by user%',[message])<>0

UNION

SELECT 'scheduled' AS Scheduled_or_manual, *

FROM msdb..sysjobhistory

WHERE step_id=0

AND PATINDEX('%The Job was invoked by schedule%',[message])<>0

AGAIN: Both the above queries are not complete solutions but should get you started.