| U.S. Presidents Quiz | 0 | - | 5.00 | 3,730,334 |
| Deadliest U.S. Wars | 0 | - | 4.89 | 191,942 |
| The Iraq War | 0 | - | 4.47 | 15,716 |
| Name a Valid U.S. President #1 | 0 | - | 4.89 | 193,989 |
| The American Revolution | 0 | - | 4.52 | 54,380 |
| Countries of Europe After World War II | 0 | - | 4.99 | 189,621 |
| 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 | 94,738 |
| Axis Occupied Countries of WWII | 0 | - | 4.99 | 230,395 |
| Countries in World War I | 0 | - | 4.88 | 229,403 |
| Neutral European Countries of WWII | 0 | - | 4.92 | 162,525 |
| Places Where Winston Churchill Said We Would Fight the Nazis | 0 | - | 4.57 | 14,655 |
| The Vietnam War | 0 | - | 4.44 | 35,688 |
| Battle to Country | 0 | - | 4.91 | 54,092 |
| U.S. Cabinet Departments | 0 | - | 4.86 | 73,156 |
| The American Civil War | 0 | - | 4.62 | 52,653 |
| Countries of Europe Before World War I | 0 | - | 4.99 | 157,692 |
| WWII First Names | 0 | - | 4.45 | 42,005 |
| U.S. Presidential Trivia #1 | 0 | - | 4.45 | 109,649 |
| U.S. Presidents by Event | 0 | - | 4.58 | 35,448 |
| Losing U.S. Presidential Candidates in History | 0 | - | 4.62 | 94,740 |
| Presidential Middle Names | 0 | - | 4.42 | 60,795 |
| U.S. Presidential Trivia #2 | 0 | - | 4.49 | 53,735 |
| Assassinated U.S. Presidents | 0 | - | 4.63 | 94,933 |
| U.S. Presidents Who Died in Office | 0 | - | 4.77 | 35,243 |
| Ten Least Guessed U.S. Presidents | 0 | - | 4.45 | 38,654 |
| Mississippi River States Empty Map Quiz | 0 | - | 4.82 | 56,366 |
| Countries in World War II | 0 | - | 4.54 | 920,125 |
| Name a Valid U.S. President #2 | 0 | - | 4.54 | 70,649 |
| Top 10 Coldest U.S. States | 0 | - | 4.94 | 125,978 |
| Top 10 Hottest U.S. States | 0 | - | 4.86 | 126,638 |
| Top 10 U.S. States with the Least Precipitation | 0 | - | 4.83 | 62,252 |
| United States Map Quiz | 0 | - | 4.98 | 4,173,242 |
| U.S. Five-Star Generals and Admirals | 0 | - | 4.33 | 8,363 |
| Countries Closest to United States A-Z | 0 | - | 4.82 | 118,818 |
| All U.S. Supreme Court Justices | 0 | - | 4.54 | 29,155 |
| All U.S. Supreme Court Justices Ever | 0 | - | 4.50 | 11,875 |
| U.S. Presidents by Picture | 0 | - | 4.87 | 428,831 |
| U.S. Vice Presidents | 0 | - | 4.39 | 137,150 |
| U.S. Governors Who Ran For President | 0 | - | 4.47 | 20,378 |
| U.S. Presidential Running Mates | 0 | - | 4.41 | 28,795 |
| First Ladies of the United States | 0 | - | 4.28 | 86,017 |
| The Abraham Lincoln Presidency | 0 | - | 4.52 | 26,332 |
| First Names of U.S. Presidents | 0 | - | 4.86 | 383,857 |
| U.S. Presidents in Order by First Letter | 0 | - | 4.32 | 77,524 |
| U.S. Vice Presidents Who Became President | 0 | - | 4.64 | 16,385 |
| Add a Letter - Make a U.S. President | 0 | - | 4.58 | 24,117 |
| Win the 1828 U.S. Presidential Election | 0 | - | 4.31 | 59,545 |
| Harvard University | 0 | - | 4.15 | 8,334 |
| Las Vegas Casinos | 0 | - | 4.13 | 38,160 |
| Six Flags Over Texas | 0 | - | 4.78 | 63,643 |
| Shortest U.S. Presidential Terms | 0 | - | 4.75 | 12,961 |
| States of the Holy Roman Empire in 1356 | 0 | - | 4.97 | 75,564 |
| Modern Countries Conquered by Alexander the Great | 0 | - | 4.89 | 114,345 |
| The Life of Winston Churchill | 0 | - | 4.16 | 11,883 |
| Important Cities in WWII | 0 | - | 4.42 | 94,262 |
| Third Most Common Language by U.S. State | 0 | - | 4.87 | 114,033 |
| Rust Belt Cities Map Quiz | 0 | - | 4.57 | 35,308 |
| Play-Doh Presidents | 0 | - | 5.00 | 82,949 |
| People in Pictures with Barack Obama | 0 | - | 4.10 | 48,111 |
| 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 | 129,717 |
| Midwestern States of the U.S. | 0 | - | 4.88 | 14,206 |
| Countries of Europe in 1650 with a Map | 0 | - | 4.95 | 70,708 |
| Modern-Day Countries of the Roman Empire on a Map | 0 | - | 4.99 | 127,020 |
| Countries of the Japanese Empire | 0 | - | 4.97 | 104,673 |
| Communist Countries in History | 0 | - | 4.63 | 498,684 |
| Top 10 Biggest Economies in the Americas | 0 | - | 4.94 | 92,938 |
| U.S. State Border Crossings | 0 | - | 4.97 | 96,952 |
| Name the U.S. National Parks | 0 | - | 4.86 | 60,580 |
| U.S. Citizenship Test Questions | 0 | - | 4.83 | 240,955 |
| Total United States Immigration by Country | 0 | - | 4.91 | 112,544 |
| U.S. Cities with the Most International Tourists | 0 | - | 4.88 | 76,043 |
| Most Common U.S. Last Names - Extreme | 0 | - | 4.94 | 175,715 |
| Names of Generations | 0 | - | 4.09 | 45,587 |
| "Do Not Travel" Countries for U.S. Citizens | 0 | - | 4.97 | 246,950 |
| U.S. Federal Agency Acronyms | 0 | - | 4.50 | 80,175 |
| U.S. Senators by State | 0 | - | 4.44 | 40,136 |
| 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 | 75,173 |
| Top 10 Non-English Languages Spoken in New York City | 0 | - | 4.85 | 66,807 |
| History of Texas | 0 | - | 4.43 | 14,690 |
| Countries Larger Than Texas but With Fewer People | 0 | - | 4.92 | 40,321 |
| Last Names in U.S. History #1 | 0 | - | 4.25 | 36,355 |
| US States Quiz | 0 | - | 5.00 | 17,018,609 |
| States of the U.S. in Alphabetical Order | 0 | - | 4.98 | 368,865 |
| Top 10 Coldest European Countries | 0 | - | 4.94 | 194,039 |
| Top 10 Hottest European Countries | 0 | - | 4.88 | 127,925 |
| Catholic Countries in Europe | 0 | - | 4.83 | 95,880 |
| Top 10 Biggest Economies in Europe | 0 | - | 4.98 | 200,942 |
| Monarchies of Europe | 0 | - | 4.90 | 99,015 |
| Category Elimination - European Geography #1 | 0 | - | 4.98 | 236,261 |
| Category Elimination - European Geography #2 | 0 | - | 4.99 | 169,205 |
| Countries of Europe in 1815 With a Map | 0 | - | 4.99 | 151,527 |
| Countries of Europe in 1848 | 0 | - | 4.98 | 85,956 |
| Countries of Europe in 1870 with a Map | 0 | - | 4.95 | 65,972 |
| Every Country of Europe Since 1815 With a Map | 0 | - | 4.97 | 71,996 |
| Countries of Europe in 1360 with a Map | 0 | - | 4.99 | 57,707 |
| Countries Italy Declared War On | 0 | - | 4.74 | 47,973 |
| Biggest Spanish Empire Countries | 0 | - | 4.91 | 117,083 |
| Modern-Day Countries of the British Empire in 1921 | 0 | - | 4.99 | 119,009 |
| Top 10 Coldest Asian Countries | 0 | - | 4.95 | 123,809 |
| Top 10 Biggest Economies in Asia | 0 | - | 4.87 | 137,678 |
| Monarchies of Asia | 0 | - | 4.97 | 71,592 |
| Category Elimination - Asian Geography #1 | 0 | - | 4.86 | 111,521 |
| Category Elimination - Asian Geography #2 | 0 | - | 4.94 | 97,898 |
| Asian Country Superlatives | 0 | - | 4.84 | 81,344 |
| Countries of the Mongol Empire on a Map | 0 | - | 4.99 | 107,681 |
| Top 10 Biggest Economies in Africa | 0 | - | 4.99 | 121,467 |
| Category Elimination - African Geography #1 | 0 | - | 4.90 | 93,569 |
| Top 10 Richest Countries in the Americas | 0 | - | 4.94 | 95,642 |
| 10 Longest Rivers in the United States | 0 | - | 4.85 | 39,431 |
| All 3,143 Counties of the United States on a Map | 0 | - | 4.97 | 336,114 |
| 10 U.S. States With The Lowest Murder Rates | 0 | - | 4.48 | 53,099 |
| Pixelated United States Map | 0 | - | 4.89 | 94,913 |
| Most-Visited Countries by Americans | 0 | - | 4.86 | 110,702 |
| Countries that Visit the United States the Most | 0 | - | 4.96 | 92,568 |
| Countries Closest to United States by Continent | 0 | - | 4.99 | 147,368 |
| Biggest Trading Partners - United States | 0 | - | 4.63 | 106,910 |
| Countries that Beat the United States | 0 | - | 4.93 | 168,870 |
| 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 | 17,001 |
| U.S. Presidents to Win the Nobel Peace Prize | 0 | - | 4.34 | 18,394 |
| U.S. Presidential Knowledge - Multiple Choice | 0 | - | 4.36 | 21,774 |
| 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 | 83,471 |
| Last Names in U.S. History #2 | 0 | - | 4.39 | 17,712 |
| The 13 Colonies Quiz | 0 | - | 4.97 | 119,168 |
| Word Scramble - U.S. States | 0 | - | 4.95 | 510,842 |
| U.S. States with the Letter Y | 0 | - | 4.86 | 112,412 |
| 10 Southernmost U.S. States | 0 | - | 4.89 | 114,442 |
| U.S. States with Short Names | 0 | - | 4.91 | 150,493 |
| U.S. States that Start with M | 0 | - | 4.93 | 188,532 |
| U.S. States By Population | 0 | - | 4.92 | 154,236 |
| U.S. States that Start with N | 0 | - | 4.95 | 172,349 |
| U.S. States with Longest Names | 0 | - | 4.85 | 44,965 |
| U.S. States by Coldest Recorded Temperature | 0 | - | 4.52 | 66,751 |
| 10 U.S. States With The Highest Murder Rates | 0 | - | 4.47 | 54,901 |
| Louisiana Purchase with a Map | 0 | - | 4.96 | 49,435 |
| US States with an Empty Map | 0 | - | 5.00 | 629,479 |
| 10 Northernmost U.S. States | 0 | - | 4.90 | 83,157 |
| U.S. States with a Unique First Letter | 0 | - | 4.96 | 88,967 |
| 10 Westernmost U.S. States | 0 | - | 4.95 | 64,590 |
| Draw All US State Borders | 0 | - | 4.99 | 141,452 |
| The Only Remaining U.S. State . . . | 0 | - | 4.93 | 66,192 |
| U.S. State Superlatives #1 | 0 | - | 4.47 | 87,707 |
| U.S. State Superlatives #2 | 0 | - | 4.53 | 40,781 |
| Top 10 Largest U.S. States by Area | 0 | - | 4.95 | 161,159 |
| Top 10 Smallest U.S. States by Area | 0 | - | 4.98 | 178,309 |
| Top 10 Poorest U.S. States by Median Income | 0 | - | 4.86 | 125,765 |
| U.S. States with the Highest Percentage of Hispanics | 0 | - | 4.85 | 69,869 |
| Top 10 Newest U.S. States | 0 | - | 4.85 | 86,713 |
| Top 10 U.S. States With the Most Tornadoes | 0 | - | 4.53 | 65,048 |
| Top 10 Least Religious U.S. States | 0 | - | 4.51 | 34,478 |
| Top 10 U.S. States by Public Transit | 0 | - | 4.74 | 64,097 |
| Top 10 Most-Visited U.S. States | 0 | - | 4.90 | 102,567 |
| 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 | 68,055 |
| Top 10 U.S. States with the Most Precipitation | 0 | - | 4.46 | 41,843 |
| Merged U.S. States | 0 | - | 4.37 | 44,455 |
| U.S. States or European Countries by Area | 0 | - | 4.95 | 97,362 |
| Top 10 Richest Countries in Europe | 0 | - | 4.90 | 151,400 |
| Biggest Trading Partners - European Union | 0 | - | 4.91 | 73,404 |
| U.S. States or European Countries by Population | 0 | - | 4.97 | 134,564 |
| Category Elimination - European Countries #1 | 0 | - | 4.90 | 91,241 |
| Countries that Bordered the USSR | 0 | - | 4.93 | 166,605 |
| Modern Day Countries of Austria-Hungary on a Map | 0 | - | 4.98 | 104,965 |
| Least Irish U.S. States | 0 | - | 4.49 | 18,414 |
| Modern Day Countries of the Dutch Empire on a Map | 0 | - | 4.87 | 61,779 |
| Countries of Iberia in History with a Map | 0 | - | 4.88 | 42,496 |
| Modern Day Countries of the Spanish Empire on a Map | 0 | - | 4.95 | 86,993 |
| The United States... or the United Kingdom? | 0 | - | 4.87 | 99,175 |
| Name the English Monarchs | 0 | - | 4.91 | 507,252 |
| Commonwealth of Nations Countries | 0 | - | 4.95 | 238,583 |
| Modern-Day Countries of the Persian Empire on a Map | 0 | - | 4.98 | 70,629 |
| Countries in the Ottoman Empire | 0 | - | 4.89 | 73,102 |
| Countries Bordering China Since 1914 | 0 | - | 4.92 | 95,919 |
| Modern Day Countries of the Japanese Empire on a Map | 0 | - | 4.98 | 90,094 |
| Biggest Mongol Empire Countries | 0 | - | 4.89 | 81,818 |
| Hindu Countries | 0 | - | 4.86 | 50,656 |
| Top 10 Richest Countries in Africa | 0 | - | 4.85 | 77,121 |
