What does "activity" mean here? It looks like referring to SCA

But SCA (Science Clubs of America) is an organization. Saying an organization is an activity sounds a bit weird.

Context:

News
Nature 148, 590-590 (15 November 1941) | doi:10.1038/148590a0


Science Clubs of America

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Abstract

A NATIONAL science activity, Science Clubs of America, is being sponsored by Science Service, the American science news service. In every locality throughout the country there will be groups active in various fields of science. Science clubs in high schools will be encouraged and given the opportunity of joining in the national movement and entering into national activities. Groups of enthusiastic amateurs in science—grinding telescope mirrors, collecting insects, breeding new plants, collecting minerals, or pursuing scores of other interesting avocations—will join in this important development. As the nucleus of Science Clubs of America, there are more than eight hundred junior clubs which have been organized during the past fourteen years by the American Institute of the City of New York. These clubs exist not only in the United States but also in Pvierto Rico, Hawaii, the Philippines, British West Indies, Alaska, Canada, and even Portugal. An advisory committee on Science Clubs of America, representing jointly the American Institute and Science Service, is being formed.

More:
http://www.nature.com/nature/journal/v148/n3759/abs/148590a0.html