From this site:

Here is a list summarizing when some common subjects first appeared in the Handbook (though many of these subjects have long appeared elsewhere, such as in the Fieldbook and in merit badge pamphlets):

Original Edition (1910)—making fire without matches
1st Edition (1911)—alcohol & tobacco, first aid, hiking, puberty
2nd Edition (1914)—conservation, knife & axe, mapping, silent signals
3rd Edition (1927)—compass, cooking without utensils
4th Edition (1940)—drug abuse
5th Edition (1948)—Scout Slogan, edible wild plants, lashings, first wilderness code of conduct ("outdoor code")
6th Edition (1959)—mouth-to-mouth resuscitation
7th Edition (1965)—first non-white faces
8th Edition (1972)—discussion of ethnic groups, modern conservation practices
9th Edition (1979)—splicing, backpacking (in addition to simple hiking)
10th Edition (1990)—bicycling, camping stoves, water filters, organ donor awareness
11th Edition (1998)—GPS (satellite ground positioning system), the Internet