Those were among the first books I ever read. Helped instill in me a lifetime habit of reading. Around the same time, there was a series called The Happy Hollisters which were the very first books I ever read on my own so they have special meaning to me, even though they are very sappy. I found a few on E-bay and got them for my kids to read.
Both my sons now read as much as I did when I was their age. I consider that my proudest achievement of a parent.
I really feel that the greatest gift a parent can give is a love of reading.