Rachel Accurso, better known as Ms. Rachel, has become a beloved figure in the world of children's education through her YouTube videos, earning billions of views.

And now Paul's free English vocabulary size test, using 100 words ... native speakers know 15,000 to 20,000 word families - or lemmas - in their first language. Word family/lemma is a root ...

Her new titles include "100 First Words," "My First Coloring Book," and "Potty Time with Bean." Unlike other "first 100 words" books, Accurso said hers is organized by usefulness, emphasizing ...