Young Hermione doing underage magic?

In Harry Potter and the Philosopher's Stone, it states that Hermione eagerly accepted her invitation to Hogwarts, and took to studying magic before she began her first year, even performing a few spells successfully.

How is this possible, with the M.O.M. laws about underage magic?

"Underage magic is any magic used by a wizard or witch who is under seventeen years of age outside of school, where children are permitted to use magic as part of their education. It has been banned under the Decree for the Reasonable Restriction of Underage Sorcery since 1875, and compliance with it is monitored and enforced by the Improper Use of Magic Office at the Ministry of Magic using the Trace Charm. Children under the age of eleven, who have little control over their abilities and no wands, are exempt from the law, though their parents are expected to keep them under control in wizarding families." (link)

Hermione would have only been eleven years old...