[TOMT][BOOK][2000s] children's book about dinosaurs in preschool

there was this book i read around 2010 or so about these dinosaurs in preschool, and it had a muted color palette with a sort of watercolor art style.

the plot was that this little kid dinosaur was too scared to go to preschool and wanted to stay with his mom, and it follows him during his first day. i remember they played with mud and had crackers for snack (during snack, there was a triceratops girl that was greedy and took all the crackers for herself). at the end of the book, the little dinosaur was happy and told his mom he enjoyed preschool.