Noun
oobleck (usually uncountable, plural ooblecks)
A mixture of cornstarch and water with unusual physical properties.
After sharing the story ‘Bartholomew and the Oobleck’, 1st and 7th grade prayer partners explored properties of matter while making their own Oobleck. Source: Internet
Three of his titles from this period were, however, chosen as Caldecott runners-up (now referred to as Caldecott Honor books): McElligot's Pool (1947), Bartholomew and the Oobleck (1949), and If I Ran the Zoo (1950). Source: Internet