The author is a Greek-speaking parent teaching his Greek-speaking children to read by visually pairing each letter with a Greek word that starts with that letter.
If you tried to teach English-speaking children with words that start with that letter in German, you'd probably confuse them quite a bit.
"We live abroad in China, and Greek is one of three languages my kids are learning."
right, but giving English-speaking kids the following would help them:
- a bear that looks like B
- an orange that looks like O
- a snake that looks like S
- a tree that looks like T
(and so on; that's just what I can think of off the top of my head)