Looks like the Skill Awards started in the 1970's. I have read some of the changes they made back then had a negative impact on membership, or maybe it was just a sign of the times. Maybe Moms and Dads didn't want their boys going out into the woods wearing uniforms and insignias, when there were slightly older boys in uniform on TV and in the newspaper going out into the jungle and getting killed. Anyway, just my opinion, don't want to get political.
I joined in late 1989 and they were in the handbook as requirements up to first class (I still have my books). I earned at least 7, at least that's how many I have in my little cedar box. In the start of 1990 we used a new handbook that did not include the skill awards for rank requirements. I remember my scoutmaster saying that we could earn them as long as they were in the troop inventory or sold at the scout store, but there would be no more afterward. I guess it was kind of a good idea to give the newer scouts something physical they could easily earn and wear. Although the requirements seemed a little easier with the new handbook. I still have both my handbooks with my scoutmasters (R.I.P.) signature, up until first class in the old book, and first class until Eagle in the new book. Always bothered me a little that my accomplishments were split between two books, especially that I liked the artwork in the old book better (Norman Rockwell vs modern photographs). Anyway, my son is now a 'Lion' and they earn something that is about he same size and shape. I did happen upon some skill awards at a flea market a few years ago and maybe they were 2 dollars each, but I passed on them not feeling all that great about buying someone else's award.