snowy blues whale and a bunch of talking-heads

Like the title implies, here are a few random illustrations from a recent project.
Published by Cambridge Uni Press, this is one of the endeavours that has kept me quiet lately.
When it comes to illustrating school books, I like to vary the drawings as much as possible and keep a little room for experimentation.These are some of the prelim sketches, can you spot the differences?
This one was dropped altogether...