What is an average weight for boys in these following grades ninth tenth 11th and 12th?

The average weights (kg) for boys, can generally vary depending on the percentile and factors such as individual growth patterns, genetics, nutrition and activity levels. While there can be considerable variation, here are some average weight ranges for different grades:

Grade 9:

- 5th percentile: 47.6 kg (105 lbs)

- 50th percentile (median): 61.2 kg (135 lbs)

- 95th percentile: 77.1 kg (170 lbs)

Grade 10:

- 5th percentile: 53.5 kg (118 lbs)

- 50th percentile (median): 68.0 kg (150 lbs)

- 95th percentile: 85.7 kg (189 lbs)

Grade 11:

- 5th percentile: 59.0 kg (130 lbs)

- 50th percentile (median): 74.8 kg (165 lbs)

- 95th percentile: 94.3 kg (208 lbs)

Grade 12:

- 5th percentile: 64.0 kg (141 lbs)

- 50th percentile (median): 81.6 kg (180 lbs)

- 95th percentile: 102.9 kg (227 lbs)

Please note that these values are general guidelines and individual weights may differ significantly from the averages. Growth and development can vary based on various factors, and there is a wide range of normal weight variations among individuals. It's always best to consult with a healthcare professional for personalized assessments and guidance related to healthy growth and development.