I know a bit about these cards, but invite anyone to fill in the gaps. Though some of these images had been used in the 1980s by View-Master, and on books, it appears that they were the first ever Sesame Street trading cards. They were sold in packets of ten cards; these packets were blue and showed Big Bird, Bert and Ernie in cartoon form with the lamppost that held the Sesame Street sign. The same trio appeared on the shop display box that held thirty-six packs, and along the sides of that box were the other characters, again in cartoon form.
I have not been able to find any other sets of cards issued by Idolmaker. The packet tells us that they were Idolmaker Inc of 50 St. Paul St. West. Suite 100, Montreal Canada H2Y 1Y8. They give the copyright to Childrens Television Workshop, Sesame Street Muppet Characters, and Jim Henson Productions, Inc, and say that they are all trademarks of the Children`s Television Workshop. It also says that the revenues would be used to help support CTW educational programmes.
This appears to be the only Sesame Street set of cards issued, though a single card, number 103, featuring the show and showing most of the cast in a group, appears in Topps "American Pie" (2011). However, the spin off series, The Muppets, which uses many of the same characters, can be found on several sets, starting with a Swedish issue of the 1970s.
Bert and Ernie are famous for their jumpers, hence their appearance here. Though I like Kermit and his frequent sparring with Miss Piggy, Bert and Ernie are the perfect friends. It is often said that they wear matching jumpers to show how well-matched they are, but the truth is that the jumpers are not identical - however they are co-ordinated, which points to them having lives and interests away from each other, but blending a good mix of each into their friendship.