* Of course, as the National Reading Panel notes, "phonics teaching is a means to an end. . In implementing systematic phonics instruction, educators must keep the end in mind and ensure that children understand the purpose of learning letter sounds and that they are able to apply these skills accurately and fluently in their daily reading and writing activities" (Washington, DC: National Institute of Child Health and Human Development, National Institute of Health, 2000, p. 10). The panel's report also states that, notwithstanding the fact that explicit, systematic, synthetic phonics is the most effective approach, there remain unanswered questions on how to make this instruction as effective as possible. For example, the panel notes that more research is needed on questions such as how long single instruction sessions should last, how many letter-sound relations should be taught, and how many months or years a phonics program should continue. Moreover, some children will learn and appropriately apply phonics skills quickly and effortlessly, while others must be taught slowly, step by step. The individual variation in any group remains a continual challenge to teacher judgment, resourcefulness, and program management skill.