Reading order
| # | Title | Published | Author | Buy on Amazon |
|---|---|---|---|---|
| 1 | What Was the Hindenburg? | 2013 | Sherri L. Smith | Buy |
| 2 | What Was the Battle of Gettysburg? | 2013 | Sherri L. Smith | Buy |
| 3 | What Was the Gold Rush? | 2013 | Sherri L. Smith | Buy |
| 4 | What Was the March on Washington? | 2013 | Sherri L. Smith | Buy |
| 5 | What Was the Boston Tea Party? | 2013 | Sherri L. Smith | Buy |
| 6 | What Was Pearl Harbor? | 2013 | Sherri L. Smith | Buy |
| 7 | What Was the Alamo? | 2013 | Sherri L. Smith | Buy |
| 8 | What Was the Underground Railroad? | 2013 | Sherri L. Smith | Buy |
| 9 | What Was Pompeii? | 2014 | Sherri L. Smith | Buy |
| 10 | What Was Ellis Island? | 2014 | Sherri L. Smith | Buy |
| 11 | What Is the Statue of Liberty? | 2014 | Sherri L. Smith | Buy |
| 12 | What Is the Panama Canal? | 2014 | Sherri L. Smith | Buy |
| 13 | What Was the Lewis and Clark Expedition? | 2014 | Sherri L. Smith | Buy |
| 14 | What Was D-Day? | 2015 | Sherri L. Smith | Buy |
| 15 | What Is the World Series? | 2015 | Sherri L. Smith | Buy |
| 16 | What Was Hurricane Katrina? | 2015 | Sherri L. Smith | Buy |
| 17 | What Were the Salem Witch Trials? | 2015 | Sherri L. Smith | Buy |
| 18 | What Is the Super Bowl? | 2015 | Sherri L. Smith | Buy |
| 19 | What Was the Great Depression? | 2015 | Sherri L. Smith | Buy |
| 20 | What Was Woodstock? | 2016 | Sherri L. Smith | Buy |
| 21 | What Are the Summer Olympics? | 2016 | Sherri L. Smith | Buy |
| 22 | What Is the Declaration of Independence? | 2016 | Sherri L. Smith | Buy |
| 23 | What Were the Twin Towers? | 2016 | Sherri L. Smith | Buy |
| 24 | What Was the Great Chicago Fire? | 2016 | Sherri L. Smith | Buy |
| 25 | What Was the San Francisco Earthquake? | 2016 | Sherri L. Smith | Buy |
| 26 | What Was the Age of the Dinosaurs? | 2017 | Sherri L. Smith | Buy |
| 27 | What Was the Wild West? | 2017 | Sherri L. Smith | Buy |
| 28 | What Is Rock and Roll? | 2017 | Sherri L. Smith | Buy |
| 29 | What Was the Ice Age? | 2017 | Sherri L. Smith | Buy |
| 30 | What Are the Ten Commandments? | 2017 | Sherri L. Smith | Buy |
| 31 | What Is the World Cup? | 2018 | Sherri L. Smith | Buy |
| 32 | What Was the Titanic? | 2018 | Sherri L. Smith | Buy |
| 33 | What Was the Holocaust? | 2018 | Sherri L. Smith | Buy |
| 34 | What Is Climate Change? | 2018 | Sherri L. Smith | Buy |
| 35 | What Is the Constitution? | 2018 | Sherri L. Smith | Buy |
| 36 | What Is the Women’s Rights Movement? | 2018 | Sherri L. Smith | Buy |
| 37 | What Were the Roaring Twenties? | 2018 | Sherri L. Smith | Buy |
| 38 | What Is the Stanley Cup? | 2019 | Sherri L. Smith | Buy |
| 39 | What Was Stonewall? | 2019 | Sherri L. Smith | Buy |
| 40 | What Is NASA? | 2019 | Sherri L. Smith | Buy |
| 41 | What Was the Vietnam War? | 2019 | Sherri L. Smith | Buy |
| 42 | What Was the Berlin Wall? | 2019 | Sherri L. Smith | Buy |
| 43 | What Were the Negro Leagues? | 2019 | Sherri L. Smith | Buy |
| 44 | What Are the Paralympic Games? | 2020 | Sherri L. Smith | Buy |
| 45 | What Was the Bombing of Hiroshima? | 2020 | Sherri L. Smith | Buy |
| 46 | What Is LEGO? | 2020 | Sherri L. Smith | Buy |
| 47 | What Is a Presidential Election? | 2020 | Sherri L. Smith | Buy |
| 48 | What Is the Civil Rights Movement? | 2020 | Sherri L. Smith | Buy |
| 49 | What Is Nintendo? | 2021 | Sherri L. Smith | Buy |
| 50 | What Was the Age of Exploration? | 2021 | Sherri L. Smith | Buy |
| 51 | What Is Congress? | 2021 | Sherri L. Smith | Buy |
| 52 | What Is Black Lives Matter? | 2021 | Sherri L. Smith | Buy |
| 53 | What Are the Winter Olympics? | 2021 | Sherri L. Smith | Buy |
| 54 | What Was the Plague? | 2021 | Sherri L. Smith | Buy |
| 55 | What Was the Harlem Renaissance? | 2021 | Sherri L. Smith | Buy |
| 56 | What Are Castles and Knights? | 2022 | Sherri L. Smith | Buy |
| 57 | What Is Juneteenth? | 2022 | Sherri L. Smith | Buy |
| 58 | What Is the AIDS Crisis? | 2022 | Sherri L. Smith | Buy |
| 59 | What Is the Supreme Court? | 2022 | Sherri L. Smith | Buy |
| 60 | What Was Reconstruction? | 2022 | Sherri L. Smith | Buy |
| 61 | What Is the Women’s World Cup? | 2023 | Sherri L. Smith | Buy |
| 62 | What Was the Tulsa Race Massacre of 1921? | 2023 | Sherri L. Smith | Buy |
| 63 | What Was World War I? | 2023 | Sherri L. Smith | Buy |
| 64 | What Was the Donner Party? | 2023 | Sherri L. Smith | Buy |
| 65 | What Was the Children’s Blizzard of 1888? | 2023 | Sherri L. Smith | Buy |
The What Was…? series (sometimes listed as “What Is…?” or “What Were…?” depending on the topic) is a massive educational nonfiction collection for young readers. With 65 installments published between 2013 and 2023, the series covers everything from the Hindenburg disaster to the civil rights movement, from LEGO to NASA.
Each book follows a consistent format: a clear question as the title, short readable chapters, black-and-white illustrations, and sidebars with extra facts. The approach makes big historical topics manageable for kids without dumbing them down. The series is part of a larger family of “Who Was/What Was/Where Is” books published by Penguin Workshop, and individual titles in this list were written or co-written by Sherri L. Smith alongside other contributors.