http://www.greatschools.org/worksheets/fourth-grade/writing/
(Printable worksheets)
http://www.teachervision.fen.com/creative-writing/printable/54688.html
(More printable worksheets for extra practice)
http://www.newton.k12.ks.us/tech/fourth_grade_internet_activities1.htm
(Games and activities online with multiple subject areas)
http://www.education.com/activity/fourth-grade/writing/
(Activities to try at home)
http://www.tlsbooks.com/fourthgradeworksheets.htm
(Writing activities)