Mystery Word

By far one of the most popular practice center is the "Mystery Word" center.  Students use letters to create 3, 4, 5 etc. words by filling in the worksheet.  Then students must use ALL of the letters to form the mystery word.  Words are always related to our content area and/or specific vocabulary.  For example, some words were: American Revolution, revolutionary, Folktale, character, Native American,  
perseverance etc.  This idea comes from Yvonne Dixon of "Sassy in Second" blog.  Be sure to check it out!