Primary and secondary pupils will have free access to the resource, split into three distinct age groups, until the end of October. There are plans to extend it to schools throughout the UK later this year, a spokesman said.
The Encyclopaedia Britannica is the oldest English encyclopedia in the world and emerged from the intellectual and scientific flourishing of the Scottish Enlightenment.
But in March its publishers said they would only make future updates online as sales have been hit by the popularity of Wikipedia and other internet reference sites.
Wikipedia is said to contain more than four million articles
in English alone, but the fact
that anyone may edit its pages has always raised concerns
However, a study by scientific journal Nature in 2005 found few differences in accuracy between Britannica and Wikipedia when it came to science articles.
Encyclopaedia Britannica said its school edition was created so that pupils could carry out research online safely.
The service also provides live training sessions, a dedicated teacher support area and new learning materials that can be used in the classroom alongside existing technology.