This is a center you can use in your classroom called Time Me.
Students start with set 1 and can build up to set 40. Each set contains 25 words with a total of 1000 words, students can learn and master. The words are editable, but they are taken from Frys high frequency words.
Students practice each set with a partner to build fluency. They practice the words first and then set the timer. They have to go as fast as they can to read the words. the graph is editable, but I time students until they mess up a word. Have students challenge themselves and beat their time and master all the words in that set. This is an easy way for students to assess themselves and the teacher can test them later after they have been practicing.