This is the original series, written from 1904-1979. See the second series (1980-1986) here. For the third Bobbsey Twins series, see here.
Authors involved: 1 Edward Stratemeyer [Literary Account Books, v. 2, #208] 2-3 Lilian C. Garis [Releases for this and below] 4-28 Howard R. Garis 29-35 Elizabeth D. Ward 36-40 Harriet S. Adams [v. 39 was c…