No one wants a repeat of the insular education received by the sons of King George V and Queen Mary.
Their eldest son, King Edward VIII, remained incurious, famously musing of the celebrated female author: "Who is this man, Bronte?". However, Prince George, Duke of Kent was always worldly, probably due to the Teck and Cambridge blood of his part-Hungarian mother,.
One way to induce a wider perspective is to be widely educated – Crown Prince Naruhito spent time in Oxford.
William and Harry's own father and uncles benefited immensely from their education outside of the UK.
Prince Andrew enjoyed his time in Canada to the extent of taking his new wife Sarah on a canoe trip years later. Prince Charles has often spoken well of his time in Australia, and the youngest of the Queen's sons, Prince Edward, is polite about his stint in New Zealand.
The American education of most European heirs is smart thinking of the times – US finance and commerce is significant.
Prince Philippe studied at Stanford University outside of San Francisco, while Prince Felipe shared a flat with his cousin Prince Pavlos of Greece during their Master degree studies in Washington. Similarly, Princess Victoria went to Yale for a time.
During her lifetime it was said Diana wanted her sons to go to an Ivy League university like Brown University, from where Princess Michael's daughter, Lady Gabriella Windsor, graduated. It is also the alma mater of Prince Albert of Monaco.