Mummies, pyramids, pharaohs! And what are hieroglyphics?

Humphrey and his classmates are studying ancient Egypt and learning about the secrets of the Nile.
(Which Humphrey learns is a river.)

But there are other mysterious secrets flying around Room 26.
Mrs. Brisbane knows that a student is leaving, but Humphrey can’t figure out which one.

And why is Mrs. Brisbane unsqueakably happy about it?

The students are forming secret clubs and making up secret codes.

Even Aldo is holding back news from Humphrey!

Humphrey’s job as a classroom pet is to help his humans solve their problems, but so many secrets are making his job HARD-HARD-HARD!

And is it good to keep secrets?

As Humphrey writes in his notebook:
Secrets, secrets everywhere
Should they stay secret, or should I share?