I work with several different yarn blends. The light acrylic yarn by Caron is extremely soft, washable, and a good selection. Color cards are here:

http://www.caron.com/color_cards/cc_simplysoft.html

http://www.caron.com/color_cards/cc_brites.html

The soft washable wool blends are made by Plymouth Yarns. These yarns are gorgeous and a few have a lovely heathered effect. Some also slightly change colors throughout, as seen in Ellie's sweater on our Gallery Page (Ellie is in her dad's arms). A good color card is provided by Yarns-And.com:

http://www.yarns-and.com/Plymouth/plyencore.htm