This study examined how much time children spend on various out-of-school activities and its relationship to their reading achievement. A total of 155 fifth graders recorded their daily activities for periods ranging from 8 to 26 weeks. The results showed that reading books was the best predictor of reading achievement, including gains in reading ability between second and fifth grade. However, most children spent little or no time reading books on most days. The study also found that time spent reading books was strongly associated with reading comprehension, vocabulary, and reading speed. The study suggested that teachers have a significant influence on how much time children spend reading books. The class that read the most books averaged 16.5 minutes per day, while the class that read the least averaged only 4.1 minutes per day. The study also found that time spent on other activities, such as eating dinner, had positive relationships with reading proficiency. However, time spent listening to music and watching television had negative relationships with reading proficiency. The study concluded that the amount of time children spend reading books is related to their reading level in the fifth grade and growth in reading proficiency from the second to the fifth grade. The study suggests that reading books is a cause, not merely a reflection, of reading proficiency. The policy implication is that increasing the amount of time children read should be a priority for both parents and teachers.This study examined how much time children spend on various out-of-school activities and its relationship to their reading achievement. A total of 155 fifth graders recorded their daily activities for periods ranging from 8 to 26 weeks. The results showed that reading books was the best predictor of reading achievement, including gains in reading ability between second and fifth grade. However, most children spent little or no time reading books on most days. The study also found that time spent reading books was strongly associated with reading comprehension, vocabulary, and reading speed. The study suggested that teachers have a significant influence on how much time children spend reading books. The class that read the most books averaged 16.5 minutes per day, while the class that read the least averaged only 4.1 minutes per day. The study also found that time spent on other activities, such as eating dinner, had positive relationships with reading proficiency. However, time spent listening to music and watching television had negative relationships with reading proficiency. The study concluded that the amount of time children spend reading books is related to their reading level in the fifth grade and growth in reading proficiency from the second to the fifth grade. The study suggests that reading books is a cause, not merely a reflection, of reading proficiency. The policy implication is that increasing the amount of time children read should be a priority for both parents and teachers.