We looked at all three books and chose Bad Eggs for Rap Point 1.
We like the way each of the drawings of the eggs helped us to understand the characters of the eggs. Non human things like eggs, cheese and champagne have been given human characteristics. We like the bad egg gang leader with the mask and also their names - Eggbert, Rotten, Cracked and Fried.
The expressions of the "characters" are important. The bottle of champagne is good because it has been made to look like a Frenchman and the Mr Cheese is exactly like a piece of Swiss cheese. His muscles are hilarious and we like the play on holey/holy.
We think the black and white drawings are effective. The lack of colour makes you focus on the actual "characters" rather than on the colours, as you would in a book for younger readers.
The drawings are simple but clever and expressive. And as Eliza said "A picture paints a million words"