I always included some type of facts practice with my 4th and 5th graders. Most frequently, I gave a quick "timed" test of 100 facts each for all four operations at three interval during the year: September, January and late May. Students were always warned ahead of time, and this encouraged practicing. We would frequently correct tests together, scores would be recorded, and tests would be sent home for parent signatures. This activity was not graded for report cards, but meant more for personal improvement and parent awareness. Every night on my assignment board I also listed 15 minutes of facts practice. Finally, one of best activities I've found for class practices was the "24 Game", where studetns had to use four numvers and simple facts to reach 24. We would have class tournaments and the motivation was really high.