The Royal Institution of Great Britain Christmas Lectures:
In the mid 1820s Michael Faraday, a former Director of the Royal Institution, initiated the first Christmas Lecture series at a time when organised education for young people was scarce. He presented a total of 19 series, establishing an exciting new venture of teaching science to young people.
The Christmas Lectures have continued annually since this time, stopping only during World War 2.
A list of speakers since 1825 can be obtainned by clicking here.
Also the Young Peoples Programme of lectures established by Lawrence Bragg in the mid 1950s (as a replacement for the afternoon lectures). Now attended by 30,000 children annually.