Final answer:
In medieval times, sons of noblemen would start their training for knighthood at around 7 years old. They would undergo formal schooling that included various subjects and physical education to prepare them for military service. This training would continue until they turned 18.
Step-by-step explanation:
In medieval times, the sons of noblemen typically began their training for knighthood around the age of seven. At this time, they would start formal schooling which included subjects such as reading, writing, mathematics, music, and physical education classes to prepare them for military service in the future. They would continue their training and education until they reached the age of 18, at which point service in the army became compulsory.