id | page_id | user_id | session_id | created

SELECT a.session_id, MIN(a.created) as start_time,
b.page_id AS last_page, b.end_time
FROM table a
INNER JOIN
   (SELECT b.session_id, MAX(b.created) as end_time, MAX(b.page_id)
   FROM table b GROUP BY b.session_id)
ON a.session_id = b.session_id GROUP BY a.session_id

SELECT  MIN(created), MAX(page_id)
FROM    modules
GROUP BY
        session_id