ELACC4L4: Determine or clarify the meaning of unknown and multiple-meaning words and phrases based on grade 4 reading and content, choosing flexibly from a range of strategies.
http://www.watchknowlearn.org/Category.aspx?CategoryID=2255
http://www.enchantedlearning.com/english/homonyms/
http://www.learninggamesforkids.com/vocabulary_games/homophones-games.html
http://www.aasd.k12.wi.us/staff/boldtkatherine/ReadingFun3-6/ReadingFun_Homophones.htm
http://www.magickeys.com/books/riddles/words.html
Homographs:
http://www.youtube.com/watch?v=777zZy2UMaA
http://www.letkidslead.com/Homographs.aspx
http://reading.pppst.com/multiplemeaning.html
Frequently Confused Words
http://4thgradeela.weebly.com/correctly-use-frequently-confused-words.html
http://www.scholastic.com/parents/blogs/scholastic-parents-raise-reader/top-20-most-commonly-confused-homophones