Time students individually. Have each student read a passage from an appropriate book aloud. See where the student is in reading speed and fluency, and make a record of it.
Bring students together and explain the rules of reading and rhythm. According to Angel, those rules are: 1) Each word is equal. The words a student does know are just as important as those they don't. 2) Relax the body. 3) Focus the mind. 4) Never repeat a word. 5) See the whole word, then go to the first syllable and use the rhythm to get through the rest of the word. 6) Read smoothly, not choppy. 7) Sit up straight.
Have all students join in beating a rhythm. Have them beat on a book or table, keeping in time with the instructor.
Beat a slow rhythm while students read aloud, each at his own pace. Each student can read his own book. The rhythm moving them forward is the important thing. Speed the pace as students read to push them forward.
Go to each student individually and repeat the rhythm exercise, making the beat faster to the point that it pushes the individual student. All other students can continue to read aloud. This helps each student learn to focus on herself and her own reading.
After several weeks of training, time the students again to check fluency.