| U.S. Presidents Quiz | 0 | - | 5.00 | 3,730,206 |
| Deadliest U.S. Wars | 0 | - | 4.89 | 191,940 |
| The Iraq War | 0 | - | 4.47 | 15,715 |
| Name a Valid U.S. President #1 | 0 | - | 4.89 | 193,981 |
| The American Revolution | 0 | - | 4.52 | 54,380 |
| Countries of Europe After World War II | 0 | - | 4.99 | 189,617 |
| U.S. Civil War Decoder | 0 | - | 4.14 | 25,345 |
| The Persian Gulf War | 0 | - | 4.02 | 8,490 |
| Vietnam War Countries | 0 | - | 4.82 | 94,734 |
| Axis Occupied Countries of WWII | 0 | - | 4.99 | 230,386 |
| Countries in World War I | 0 | - | 4.88 | 229,396 |
| Neutral European Countries of WWII | 0 | - | 4.92 | 162,520 |
| Places Where Winston Churchill Said We Would Fight the Nazis | 0 | - | 4.57 | 14,655 |
| The Vietnam War | 0 | - | 4.44 | 35,685 |
| Battle to Country | 0 | - | 4.91 | 54,088 |
| U.S. Cabinet Departments | 0 | - | 4.86 | 73,147 |
| The American Civil War | 0 | - | 4.62 | 52,651 |
| Countries of Europe Before World War I | 0 | - | 4.99 | 157,684 |
| WWII First Names | 0 | - | 4.45 | 42,005 |
| U.S. Presidential Trivia #1 | 0 | - | 4.45 | 109,644 |
| U.S. Presidents by Event | 0 | - | 4.58 | 35,444 |
| Losing U.S. Presidential Candidates in History | 0 | - | 4.62 | 94,738 |
| Presidential Middle Names | 0 | - | 4.42 | 60,794 |
| U.S. Presidential Trivia #2 | 0 | - | 4.49 | 53,734 |
| Assassinated U.S. Presidents | 0 | - | 4.63 | 94,932 |
| U.S. Presidents Who Died in Office | 0 | - | 4.77 | 35,241 |
| Ten Least Guessed U.S. Presidents | 0 | - | 4.45 | 38,654 |
| Mississippi River States Empty Map Quiz | 0 | - | 4.82 | 56,365 |
| Countries in World War II | 0 | - | 4.54 | 920,098 |
| Name a Valid U.S. President #2 | 0 | - | 4.54 | 70,648 |
| Top 10 Coldest U.S. States | 0 | - | 4.94 | 125,969 |
| Top 10 Hottest U.S. States | 0 | - | 4.86 | 126,633 |
| Top 10 U.S. States with the Least Precipitation | 0 | - | 4.83 | 62,248 |
| United States Map Quiz | 0 | - | 4.98 | 4,173,197 |
| U.S. Five-Star Generals and Admirals | 0 | - | 4.33 | 8,363 |
| Countries Closest to United States A-Z | 0 | - | 4.82 | 118,817 |
| All U.S. Supreme Court Justices | 0 | - | 4.54 | 29,155 |
| All U.S. Supreme Court Justices Ever | 0 | - | 4.50 | 11,874 |
| U.S. Presidents by Picture | 0 | - | 4.87 | 428,819 |
| U.S. Vice Presidents | 0 | - | 4.39 | 137,146 |
| U.S. Governors Who Ran For President | 0 | - | 4.47 | 20,378 |
| U.S. Presidential Running Mates | 0 | - | 4.41 | 28,794 |
| First Ladies of the United States | 0 | - | 4.28 | 86,016 |
| The Abraham Lincoln Presidency | 0 | - | 4.52 | 26,332 |
| First Names of U.S. Presidents | 0 | - | 4.86 | 383,844 |
| U.S. Presidents in Order by First Letter | 0 | - | 4.32 | 77,522 |
| U.S. Vice Presidents Who Became President | 0 | - | 4.64 | 16,384 |
| Add a Letter - Make a U.S. President | 0 | - | 4.58 | 24,117 |
| Win the 1828 U.S. Presidential Election | 0 | - | 4.31 | 59,529 |
| Harvard University | 0 | - | 4.15 | 8,334 |
| Las Vegas Casinos | 0 | - | 4.13 | 38,159 |
| Six Flags Over Texas | 0 | - | 4.78 | 63,641 |
| Shortest U.S. Presidential Terms | 0 | - | 4.75 | 12,960 |
| States of the Holy Roman Empire in 1356 | 0 | - | 4.97 | 75,562 |
| Modern Countries Conquered by Alexander the Great | 0 | - | 4.89 | 114,323 |
| The Life of Winston Churchill | 0 | - | 4.16 | 11,883 |
| Important Cities in WWII | 0 | - | 4.42 | 94,258 |
| Third Most Common Language by U.S. State | 0 | - | 4.87 | 114,031 |
| Rust Belt Cities Map Quiz | 0 | - | 4.57 | 35,308 |
| Play-Doh Presidents | 0 | - | 5.00 | 82,947 |
| People in Pictures with Barack Obama | 0 | - | 4.10 | 48,108 |
| California A-Z | 0 | - | 4.49 | 28,854 |
| 100 Most Influential Figures in U.S. History | 0 | - | 4.20 | 45,250 |
| Confederate States of the U.S. Civil War | 0 | - | 4.91 | 129,716 |
| Midwestern States of the U.S. | 0 | - | 4.88 | 14,205 |
| Countries of Europe in 1650 with a Map | 0 | - | 4.95 | 70,701 |
| Modern-Day Countries of the Roman Empire on a Map | 0 | - | 4.99 | 127,016 |
| Countries of the Japanese Empire | 0 | - | 4.97 | 104,670 |
| Communist Countries in History | 0 | - | 4.63 | 498,668 |
| Top 10 Biggest Economies in the Americas | 0 | - | 4.94 | 92,936 |
| U.S. State Border Crossings | 0 | - | 4.97 | 96,948 |
| Name the U.S. National Parks | 0 | - | 4.86 | 60,578 |
| U.S. Citizenship Test Questions | 0 | - | 4.83 | 240,949 |
| Total United States Immigration by Country | 0 | - | 4.91 | 112,536 |
| U.S. Cities with the Most International Tourists | 0 | - | 4.88 | 76,041 |
| Most Common U.S. Last Names - Extreme | 0 | - | 4.94 | 175,709 |
| Names of Generations | 0 | - | 4.09 | 45,585 |
| "Do Not Travel" Countries for U.S. Citizens | 0 | - | 4.97 | 246,938 |
| U.S. Federal Agency Acronyms | 0 | - | 4.50 | 80,174 |
| U.S. Senators by State | 0 | - | 4.44 | 40,134 |
| The Thomas Jefferson Presidency | 0 | - | 4.26 | 13,788 |
| Random U.S. Vice President to President | 0 | - | 4.39 | 30,776 |
| The John Adams Presidency | 0 | - | 4.12 | 8,798 |
| The Theodore Roosevelt Presidency | 0 | - | 4.39 | 7,784 |
| U.S. Vice Presidential Trivia | 0 | - | 4.26 | 12,940 |
| History of Florida | 0 | - | 4.45 | 9,877 |
| Cities and Towns of Massachusetts | 0 | - | 4.93 | 75,168 |
| Top 10 Non-English Languages Spoken in New York City | 0 | - | 4.85 | 66,806 |
| History of Texas | 0 | - | 4.43 | 14,690 |
| Countries Larger Than Texas but With Fewer People | 0 | - | 4.92 | 40,319 |
| Last Names in U.S. History #1 | 0 | - | 4.25 | 36,355 |
| US States Quiz | 0 | - | 5.00 | 17,017,892 |
| States of the U.S. in Alphabetical Order | 0 | - | 4.98 | 368,847 |
| Top 10 Coldest European Countries | 0 | - | 4.94 | 194,034 |
| Top 10 Hottest European Countries | 0 | - | 4.88 | 127,920 |
| Catholic Countries in Europe | 0 | - | 4.83 | 95,875 |
| Top 10 Biggest Economies in Europe | 0 | - | 4.98 | 200,937 |
| Monarchies of Europe | 0 | - | 4.90 | 99,012 |
| Category Elimination - European Geography #1 | 0 | - | 4.98 | 236,247 |
| Category Elimination - European Geography #2 | 0 | - | 4.99 | 169,197 |
| Countries of Europe in 1815 With a Map | 0 | - | 4.99 | 151,524 |
| Countries of Europe in 1848 | 0 | - | 4.98 | 85,938 |
| Countries of Europe in 1870 with a Map | 0 | - | 4.95 | 65,969 |
| Every Country of Europe Since 1815 With a Map | 0 | - | 4.97 | 71,991 |
| Countries of Europe in 1360 with a Map | 0 | - | 4.99 | 57,706 |
| Countries Italy Declared War On | 0 | - | 4.74 | 47,923 |
| Biggest Spanish Empire Countries | 0 | - | 4.91 | 117,077 |
| Modern-Day Countries of the British Empire in 1921 | 0 | - | 4.99 | 119,003 |
| Top 10 Coldest Asian Countries | 0 | - | 4.95 | 123,806 |
| Top 10 Biggest Economies in Asia | 0 | - | 4.87 | 137,666 |
| Monarchies of Asia | 0 | - | 4.97 | 71,592 |
| Category Elimination - Asian Geography #1 | 0 | - | 4.86 | 111,518 |
| Category Elimination - Asian Geography #2 | 0 | - | 4.94 | 97,895 |
| Asian Country Superlatives | 0 | - | 4.84 | 81,341 |
| Countries of the Mongol Empire on a Map | 0 | - | 4.99 | 107,674 |
| Top 10 Biggest Economies in Africa | 0 | - | 4.99 | 121,464 |
| Category Elimination - African Geography #1 | 0 | - | 4.90 | 93,564 |
| Top 10 Richest Countries in the Americas | 0 | - | 4.94 | 95,630 |
| 10 Longest Rivers in the United States | 0 | - | 4.85 | 39,428 |
| All 3,143 Counties of the United States on a Map | 0 | - | 4.97 | 336,085 |
| 10 U.S. States With The Lowest Murder Rates | 0 | - | 4.48 | 53,098 |
| Pixelated United States Map | 0 | - | 4.89 | 94,910 |
| Most-Visited Countries by Americans | 0 | - | 4.86 | 110,696 |
| Countries that Visit the United States the Most | 0 | - | 4.96 | 92,563 |
| Countries Closest to United States by Continent | 0 | - | 4.99 | 147,361 |
| Biggest Trading Partners - United States | 0 | - | 4.63 | 106,910 |
| Countries that Beat the United States | 0 | - | 4.93 | 168,861 |
| Red State or Blue State Trait? | 0 | - | 4.42 | 55,763 |
| The Franklin D. Roosevelt Presidency | 0 | - | 4.38 | 24,085 |
| The George Washington Presidency | 0 | - | 4.03 | 14,621 |
| Franklin... or Theodore Roosevelt | 0 | - | 4.35 | 17,000 |
| U.S. Presidents to Win the Nobel Peace Prize | 0 | - | 4.34 | 18,394 |
| U.S. Presidential Knowledge - Multiple Choice | 0 | - | 4.36 | 21,773 |
| History of California | 0 | - | 4.40 | 18,801 |
| History of Georgia (U.S. State) | 0 | - | 4.30 | 13,267 |
| History of Illinois | 0 | - | 4.24 | 11,259 |
| History of Maryland | 0 | - | 4.06 | 6,737 |
| History of Massachusetts | 0 | - | 4.14 | 8,438 |
| History of Michigan | 0 | - | 4.26 | 6,987 |
| History of New York | 0 | - | 4.36 | 16,427 |
| History of New Jersey | 0 | - | 4.38 | 7,316 |
| History of Ohio | 0 | - | 4.14 | 7,388 |
| History of Tennessee | 0 | - | 4.29 | 7,690 |
| History of Washington State | 0 | - | 4.27 | 6,918 |
| U.S. History for Dummies | 0 | - | 4.47 | 83,468 |
| Last Names in U.S. History #2 | 0 | - | 4.39 | 17,712 |
| The 13 Colonies Quiz | 0 | - | 4.97 | 119,165 |
| Word Scramble - U.S. States | 0 | - | 4.95 | 510,822 |
| U.S. States with the Letter Y | 0 | - | 4.86 | 112,404 |
| 10 Southernmost U.S. States | 0 | - | 4.89 | 114,436 |
| U.S. States with Short Names | 0 | - | 4.91 | 150,487 |
| U.S. States that Start with M | 0 | - | 4.93 | 188,526 |
| U.S. States By Population | 0 | - | 4.92 | 154,228 |
| U.S. States that Start with N | 0 | - | 4.95 | 172,347 |
| U.S. States with Longest Names | 0 | - | 4.85 | 44,962 |
| U.S. States by Coldest Recorded Temperature | 0 | - | 4.52 | 66,751 |
| 10 U.S. States With The Highest Murder Rates | 0 | - | 4.47 | 54,899 |
| Louisiana Purchase with a Map | 0 | - | 4.96 | 49,433 |
| US States with an Empty Map | 0 | - | 5.00 | 629,448 |
| 10 Northernmost U.S. States | 0 | - | 4.90 | 83,155 |
| U.S. States with a Unique First Letter | 0 | - | 4.96 | 88,963 |
| 10 Westernmost U.S. States | 0 | - | 4.95 | 64,588 |
| Draw All US State Borders | 0 | - | 4.99 | 141,436 |
| The Only Remaining U.S. State . . . | 0 | - | 4.93 | 66,186 |
| U.S. State Superlatives #1 | 0 | - | 4.47 | 87,706 |
| U.S. State Superlatives #2 | 0 | - | 4.53 | 40,781 |
| Top 10 Largest U.S. States by Area | 0 | - | 4.95 | 161,157 |
| Top 10 Smallest U.S. States by Area | 0 | - | 4.98 | 178,306 |
| Top 10 Poorest U.S. States by Median Income | 0 | - | 4.86 | 125,760 |
| U.S. States with the Highest Percentage of Hispanics | 0 | - | 4.85 | 69,869 |
| Top 10 Newest U.S. States | 0 | - | 4.85 | 86,711 |
| Top 10 U.S. States With the Most Tornadoes | 0 | - | 4.53 | 65,048 |
| Top 10 Least Religious U.S. States | 0 | - | 4.51 | 34,475 |
| Top 10 U.S. States by Public Transit | 0 | - | 4.74 | 64,093 |
| Top 10 Most-Visited U.S. States | 0 | - | 4.90 | 102,565 |
| U.S. States with the Most Immigrants | 0 | - | 4.85 | 83,095 |
| Top 10 U.S. States Where the Rent is Too Dang High | 0 | - | 4.85 | 68,053 |
| Top 10 U.S. States with the Most Precipitation | 0 | - | 4.46 | 41,841 |
| Merged U.S. States | 0 | - | 4.37 | 44,453 |
| U.S. States or European Countries by Area | 0 | - | 4.95 | 97,354 |
| Top 10 Richest Countries in Europe | 0 | - | 4.90 | 151,393 |
| Biggest Trading Partners - European Union | 0 | - | 4.91 | 73,402 |
| U.S. States or European Countries by Population | 0 | - | 4.97 | 134,562 |
| Category Elimination - European Countries #1 | 0 | - | 4.90 | 91,241 |
| Countries that Bordered the USSR | 0 | - | 4.93 | 166,601 |
| Modern Day Countries of Austria-Hungary on a Map | 0 | - | 4.98 | 104,960 |
| Least Irish U.S. States | 0 | - | 4.49 | 18,413 |
| Modern Day Countries of the Dutch Empire on a Map | 0 | - | 4.87 | 61,776 |
| Countries of Iberia in History with a Map | 0 | - | 4.88 | 42,492 |
| Modern Day Countries of the Spanish Empire on a Map | 0 | - | 4.95 | 86,991 |
| The United States... or the United Kingdom? | 0 | - | 4.87 | 99,175 |
| Name the English Monarchs | 0 | - | 4.91 | 507,231 |
| Commonwealth of Nations Countries | 0 | - | 4.95 | 238,577 |
| Modern-Day Countries of the Persian Empire on a Map | 0 | - | 4.98 | 70,626 |
| Countries in the Ottoman Empire | 0 | - | 4.89 | 73,098 |
| Countries Bordering China Since 1914 | 0 | - | 4.92 | 95,914 |
| Modern Day Countries of the Japanese Empire on a Map | 0 | - | 4.98 | 90,088 |
| Biggest Mongol Empire Countries | 0 | - | 4.89 | 81,815 |
| Hindu Countries | 0 | - | 4.86 | 50,654 |
| Top 10 Richest Countries in Africa | 0 | - | 4.85 | 77,120 |
