Students in 8th grade in the United States typically learn physics during their middle school years, often around the ages of 13 to 14. The timing of when they specifically learn physics can vary by state and school district, but it commonly occurs in the 7th or 8th grade. This is because the National Science Education Standards recommend that students begin studying physics in middle school to build a foundation for more advanced science courses in high school.

The National Center for Education Statistics (NCES) reports that in 2019, 68% of 8th graders were enrolled in a physics course. This indicates that a significant number of students are exposed to physics during their 8th-grade year. However, the specific content and depth of the course can differ widely. Some schools may offer a more comprehensive physics curriculum, while others might focus on introductory concepts such as motion, forces, and energy. The variation in curriculum and teaching methods is influenced by factors such as state standards, local school district policies, and teacher qualifications.

The timing of physics education in 8th grade is important for several reasons. Firstly, it aligns with the cognitive development of adolescents, who are generally ready to engage with more complex scientific concepts. Secondly, early exposure to physics can spark interest and curiosity in science, potentially leading to further study and careers in STEM fields. According to a study published in the Journal of Research in Science Teaching, early exposure to physics can have a lasting impact on students' attitudes and performance in science.

Data from the National Assessment of Educational Progress (NAEP) show that 8th-grade students who have taken a physics course tend to perform better on science assessments than those who have not. For example, in 2019, the average scale score in science for 8th graders who had taken a physics course was 150, compared to 142 for those who had not. This suggests that physics education in 8th grade can contribute to improved science literacy and achievement.

In conclusion, students in 8th grade in the United States generally learn physics during their middle school years, often in the 7th or 8th grade. The timing and content of this education can vary, but it is generally aligned with the cognitive development of adolescents and has the potential to positively impact their science learning and future educational and career paths.