I wonder why the sea is salty and other questions about the ocean

The Oceans Atlas

1982

I Wonder Why Camels Have Humps

1993

I Wonder Why the Wind Blows

1994

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I wonder why the sea is salty and other questions about the ocean

1994

Odious Oceans

1999

Violent Volcanoes

1999

The Mystery of the Bermuda Triangle

1999

Stormy Weather (Horrible Geography)

1999

Earth Shattering Earthquakes (Horrible Geography)

2000

Eruption!

2000

Raging Rivers (Horrible Geography)

2000

Earth & Space

2001

Bloomin' Rainforests (Horrible Geography)

2001

Harriet Tubman

2004

Cleopatra

2005

This Is My Faith

2006

Adventure Stories

2013

Exploring rivers

2014

Exploring coasts

2014

Celebrating Birth Around the World

2015