Ooh a Great Wall! Perhaps add some other answers for Biff category. I’ve always known this series as either Oxford Reading Tree or simply Biff, Chip and Kipper :) x

Bit too fiendish for me....

I would change the answer for Biff, Chip, Kipper and Floppy. The Magic Key was based on the Oxford reading tree books. There is also now a Biff and Chip Cbeebies programme with the same characters which some will reference (I now have the theme of that in my head. Grrr).

Just to let you know, I had never heard of it, but apparently Accordion is spelt with an -on just like the musical instrument.