Every professional should have a library of resources.  To remain effective in the classroom, you will probably call on your knowledge of Dalcroze, Orff, Kodály, and Gordon, to name a few.  Listed below are a selected list of texts that comprise  a basic elementary music education library any, (many more could be cited).

Folk Song Anthologies

• Locke, Eleanor G. Sail Away, (New York: Boosey and Hawkes, 1988)

• Erdei, Peter and Katalin Komlos 150 American Folk Songs, (New York: Boosey and Hawkes, 1974)

• Johnson, Richard. Folk Songs North America Sings, (Toronto: Caeat Music, 1984). Distributed by Hal Leonard.

• Jones, Bessie and Bess Lomax Hawes, Step it Down (Athens, GA: University of Georgia Press, 1987)

• Jill Trinka's Collection of Play parties, singing games, and American folksongs.

• Rao, Doreen We Will Sing. (New York: Boosey and Hawkes, 1993)

Music Education Texts

• Frazee, Jane. Discovering Orff, (New York: Schott, 1987)
  A standard text for implementing the Orff process into your classroom.
   

• Steen, Arvida, Exploring Orff, (New York:  Schott, 1992)
  A companion text to Frazee's text.  Provides more lessons and idea for those interested in Orff.
   

• Chosky, Lois. The Kodály Method, (Englewood Cliffs, NJ: Prentice Hall, 1988)
  The definitive guide to implementing the Kodály method.  Provides step by step instruction as to how to sequence daily, weekly, monthly, and yearly lesson planning.  A great resource.
   

• Chosky, Lois, Robert M. Abramson, Avon E. Gillespie, and David Woods, Teaching Music in the Twentieth Century, (Englewood Cliffs, NJ: Prentice Hall, 1986)
  A little bit of everything.  This text provides an overview of Orff, Kodály, and Dalcroze.  If you can only afford one text, this is one of the best for your money.
   

• Valerio, Wendy, H., Alison M. Reynolds, Beth M. Bolton, Cynthia C. Taggart, and Edwin E. Gordon. Music Play. (Chicago: GIA Publications, 1998)
  Recently, Gordon's learning theory has piqued the profession's interest.  While geared to early childhood music specialists, this text provides the basics to understanding Gordon's ideas.
   

• Shehan-Campbell, Patricia, Carol Scott-Kassner. Music In Childhood, 2nd (New York: Schirmer Books, 2001).
  A text that covers traditional methodologies/processes for making music with children but provides opportunities for developing each specialist's personal method of musical interaction.  This is a great resource.
   

• Wiggins, Jackie. Teaching for Musical Understanding. (New York: McGraw-Hill, 2001).
  A wonderful text that concentrates on child-centered music instruction.  This is my personal favorite.