| The Persian Gulf War | 0 | - | 4.02 | 8,471 |
| Countries of the Japanese Empire | 0 | - | 4.97 | 104,450 |
| The American Revolution | 0 | - | 4.52 | 54,314 |
| U.S. Presidents by Picture | 0 | - | 4.87 | 427,730 |
| Neutral European Countries of WWII | 0 | - | 4.91 | 161,974 |
| Name a Valid U.S. President #1 | 0 | - | 4.89 | 193,144 |
| Countries of Europe After World War II | 0 | - | 4.99 | 188,993 |
| Countries of Europe Before World War I | 0 | - | 4.99 | 157,105 |
| The Vietnam War | 0 | - | 4.44 | 35,611 |
| Confederate States of the U.S. Civil War | 0 | - | 4.91 | 129,488 |
| Vietnam War Countries | 0 | - | 4.82 | 94,466 |
| U.S. Civil War Decoder | 0 | - | 4.14 | 25,317 |
| U.S. Presidents Quiz | 0 | - | 5.00 | 3,715,696 |
| Random U.S. States on a Map | 0 | - | 4.96 | 628,781 |
| Asian Countries with the Most Christians | 0 | - | 4.86 | 97,684 |
| Top 10 Biggest Economies in Asia | 0 | - | 4.87 | 136,290 |
| Countries of the Mongol Empire on a Map | 0 | - | 4.99 | 107,262 |
| Deadliest U.S. Wars | 0 | - | 4.89 | 191,467 |
| Countries in the Ottoman Empire | 0 | - | 4.89 | 72,909 |
| Biggest Mongol Empire Countries | 0 | - | 4.89 | 81,526 |
| US Presidents - One Minute Sprint | 0 | - | 4.41 | 305,808 |
| Name a Valid U.S. President #2 | 0 | - | 4.54 | 70,384 |
| East Asia Map Quiz | 0 | - | 4.99 | 1,450,718 |
| Asia Map Quiz | 0 | - | 4.99 | 922,078 |
| Modern-Day Countries of the Persian Empire on a Map | 0 | - | 4.98 | 70,305 |
| Biggest Trading Partners - Turkey | 0 | - | 4.81 | 51,019 |
| Modern-Day Countries of the Ottoman Empire on a Map | 0 | - | 4.96 | 83,175 |
| Biggest Trading Partners - China | 0 | - | 4.95 | 75,373 |
| Countries Bordering China Since 1914 | 0 | - | 4.92 | 95,685 |
| Modern Day Countries of the Japanese Empire on a Map | 0 | - | 4.98 | 89,693 |
| Countries with the Most Hindus | 0 | - | 4.90 | 123,342 |
| Hindu Countries | 0 | - | 4.87 | 50,410 |
| United States Map Quiz | 0 | - | 4.98 | 4,166,410 |
| Arms Exports - United States | 0 | - | 4.77 | 62,610 |
| All U.S. Supreme Court Justices | 0 | - | 4.54 | 29,125 |
| All U.S. Supreme Court Justices Ever | 0 | - | 4.50 | 11,843 |
| The Franklin D. Roosevelt Presidency | 0 | - | 4.43 | 24,016 |
| First Names of U.S. Presidents | 0 | - | 4.86 | 382,927 |
| The John F. Kennedy Presidency | 0 | - | 4.47 | 43,865 |
| Six Flags Over Texas | 0 | - | 4.78 | 63,518 |
| Category Elimination - U.S. States #1 | 0 | - | 4.88 | 221,829 |
| Category Elimination - U.S. States #2 | 0 | - | 4.83 | 135,013 |
| South and Central Asia Map Quiz | 0 | - | 4.94 | 99,608 |
| Middle East Map Quiz | 0 | - | 4.99 | 1,385,837 |
| Third Most Common Language by U.S. State | 0 | - | 4.87 | 113,892 |
| The George W. Bush Presidency | 0 | - | 4.06 | 32,241 |
| U.S. President Scramble | 0 | - | 4.40 | 117,291 |
| U.S. Presidents With Facial Hair By Picture | 0 | - | 4.48 | 23,281 |
| People in Pictures with Barack Obama | 0 | - | 4.10 | 48,014 |
| California A-Z | 0 | - | 4.49 | 28,820 |
| Midwestern States of the U.S. | 0 | - | 4.88 | 14,014 |
| Countries of Europe in 1650 with a Map | 0 | - | 4.95 | 69,960 |
| Countries of the Soviet Union | 0 | - | 4.98 | 195,317 |
| Soviet Union Country Quiz | 0 | - | 4.91 | 80,977 |
| Flags of Asia Quiz | 0 | - | 4.99 | 617,521 |
| East Asia Cities Map Quiz | 0 | - | 4.96 | 110,564 |
| 10 Biggest Asian Countries by Area | 0 | - | 4.97 | 154,265 |
| 10 Southernmost Countries in Asia | 0 | - | 4.97 | 99,633 |
| 10 Easternmost Countries in Asia | 0 | - | 4.99 | 108,892 |
| Countries of Asia in 1900 | 0 | - | 4.50 | 58,163 |
| Countries of Asia with Two or More Words | 0 | - | 4.96 | 127,466 |
| Asian Countries Ending in "IA" | 0 | - | 4.96 | 108,018 |
| Countries of the Middle East | 0 | - | 4.96 | 202,106 |
| U.S. State Border Crossings | 0 | - | 4.97 | 96,723 |
| Name the U.S. National Parks | 0 | - | 4.86 | 60,269 |
| U.S. Citizenship Test Questions | 0 | - | 4.83 | 240,507 |
| Total United States Immigration by Country | 0 | - | 4.91 | 112,074 |
| U.S. Cities with the Most International Tourists | 0 | - | 4.88 | 75,751 |
| Most Common U.S. Last Names - Extreme | 0 | - | 4.94 | 175,156 |
| "Do Not Travel" Countries for U.S. Citizens | 0 | - | 4.97 | 245,488 |
| U.S. Federal Agency Acronyms | 0 | - | 4.50 | 80,082 |
| U.S. Cabinet Departments | 0 | - | 4.86 | 73,006 |
| U.S. Senators by State | 0 | - | 4.44 | 40,040 |
| History of Florida | 0 | - | 4.45 | 9,858 |
| Cities and Towns of Massachusetts | 0 | - | 4.92 | 74,671 |
| Top 10 Non-English Languages Spoken in New York City | 0 | - | 4.85 | 66,540 |
| History of Texas | 0 | - | 4.43 | 14,670 |
| Countries Larger Than Texas but With Fewer People | 0 | - | 4.92 | 40,140 |
| Last Names in U.S. History #1 | 0 | - | 4.25 | 36,302 |
| US States Quiz | 0 | - | 5.00 | 16,948,685 |
| States of the U.S. in Alphabetical Order | 0 | - | 4.98 | 368,090 |
| Top 10 Biggest Economies in Europe | 0 | - | 4.98 | 200,119 |
| Countries of Europe in 1815 With a Map | 0 | - | 4.99 | 150,990 |
| Every Country of Europe Since 1815 With a Map | 0 | - | 4.98 | 71,526 |
| Modern Day Countries of Nazi Germany on a Map | 0 | - | 4.97 | 145,227 |
| Countries Italy Declared War On | 0 | - | 4.75 | 43,526 |
| Countries in the Byzantine Empire | 0 | - | 4.95 | 72,339 |
| Biggest Spanish Empire Countries | 0 | - | 4.91 | 116,488 |
| Modern-Day Countries of the British Empire in 1921 | 0 | - | 4.99 | 118,309 |
| 10 Asian Countries with the Most Tourists | 0 | - | 4.89 | 106,509 |
| Top 10 Coldest Asian Countries | 0 | - | 4.95 | 123,589 |
| Asian Countries with the Shortest Names | 0 | - | 4.97 | 135,788 |
| "Stan" Countries - Map Quiz | 0 | - | 4.98 | 136,874 |
| Asian Countries Americans Travel to the Most | 0 | - | 4.75 | 60,117 |
| Top 10 Richest Countries in Asia | 0 | - | 4.74 | 105,986 |
| Pixelated Asia Map | 0 | - | 4.90 | 73,571 |
| Monarchies of Asia | 0 | - | 4.97 | 71,343 |
| Name a Valid Asian Country | 0 | - | 4.98 | 121,439 |
| Asian Country Superlatives | 0 | - | 4.84 | 81,136 |
| Countries Closest to the Persian Gulf | 0 | - | 4.93 | 83,582 |
| Qatar Country Quiz | 0 | - | 4.86 | 31,631 |
| Jordan Country Quiz | 0 | - | 4.86 | 31,977 |
| Countries with the Most Arabic Speakers | 0 | - | 4.92 | 80,592 |
| Countries in Southeast Asia With an Empty Map | 0 | - | 4.97 | 101,849 |
| China Cities Map Quiz | 0 | - | 4.94 | 105,656 |
| Provinces of China Map Quiz | 0 | - | 4.92 | 94,164 |
| Japan Country Quiz | 0 | - | 4.93 | 142,984 |
| Countries Kim Jong Un Has Been To | 0 | - | 4.95 | 33,162 |
| Countries that Bordered British India with an Empty Map | 0 | - | 4.69 | 55,574 |
| Countries with the Most Ascents of Mount Everest | 0 | - | 4.95 | 58,446 |
| Nepal Country Quiz | 0 | - | 4.95 | 37,887 |
| African Countries with the Most Christians | 0 | - | 4.94 | 75,893 |
| Top 10 Biggest Economies in Africa | 0 | - | 4.99 | 120,976 |
| Biggest Trading Partners – Australia | 0 | - | 4.93 | 61,817 |
| 10 Longest Rivers in the United States | 0 | - | 4.85 | 39,304 |
| All 3,143 Counties of the United States on a Map | 0 | - | 4.97 | 334,098 |
| 10 U.S. States With The Lowest Murder Rates | 0 | - | 4.48 | 52,563 |
| Pixelated United States Map | 0 | - | 4.88 | 94,607 |
| Most-Visited Countries by Americans | 0 | - | 4.86 | 110,172 |
| Countries that Visit the United States the Most | 0 | - | 4.96 | 92,176 |
| Countries Closest to United States by Continent | 0 | - | 4.99 | 146,894 |
| Biggest Trading Partners - United States | 0 | - | 4.63 | 106,778 |
| Countries that Beat the United States | 0 | - | 4.93 | 168,177 |
| U.S. Bill of Rights | 0 | - | 4.53 | 32,573 |
| Presidential Actors | 0 | - | 4.36 | 19,218 |
| U.S. Presidents to Win the Nobel Peace Prize | 0 | - | 4.34 | 18,346 |
| The Barack Obama Presidency | 0 | - | 4.13 | 25,459 |
| History of California | 0 | - | 4.40 | 18,778 |
| History of Georgia (U.S. State) | 0 | - | 4.30 | 13,247 |
| History of Illinois | 0 | - | 4.24 | 11,244 |
| History of Maryland | 0 | - | 4.06 | 6,715 |
| History of Massachusetts | 0 | - | 4.14 | 8,413 |
| History of Michigan | 0 | - | 4.26 | 6,968 |
| History of New York | 0 | - | 4.36 | 16,395 |
| History of New Jersey | 0 | - | 4.38 | 7,295 |
| History of Ohio | 0 | - | 4.14 | 7,369 |
| History of Tennessee | 0 | - | 4.29 | 7,678 |
| History of Washington State | 0 | - | 4.27 | 6,894 |
| U.S. History for Dummies | 0 | - | 4.47 | 83,281 |
| Last Names in U.S. History #2 | 0 | - | 4.39 | 17,667 |
| The American Civil War | 0 | - | 4.62 | 52,557 |
| The 13 Colonies Quiz | 0 | - | 4.97 | 118,691 |
| Word Scramble - U.S. States | 0 | - | 4.95 | 508,728 |
| U.S. States with the Letter Y | 0 | - | 4.85 | 111,916 |
| 10 Southernmost U.S. States | 0 | - | 4.89 | 113,915 |
| U.S. States with Short Names | 0 | - | 4.91 | 149,541 |
| U.S. States that Start with M | 0 | - | 4.93 | 187,907 |
| U.S. States By Population | 0 | - | 4.92 | 153,891 |
| U.S. States that Start with N | 0 | - | 4.95 | 171,905 |
| U.S. States with Longest Names | 0 | - | 4.84 | 44,704 |
| U.S. States by Coldest Recorded Temperature | 0 | - | 4.52 | 66,656 |
| 10 U.S. States With The Highest Murder Rates | 0 | - | 4.47 | 54,665 |
| Louisiana Purchase with a Map | 0 | - | 4.96 | 49,016 |
| US States with an Empty Map | 0 | - | 5.00 | 626,994 |
| 10 Northernmost U.S. States | 0 | - | 4.90 | 82,896 |
| States in a Tank of the U.S. Map | 0 | - | 4.47 | 31,383 |
| U.S. States with a Unique First Letter | 0 | - | 4.96 | 88,656 |
| 10 Westernmost U.S. States | 0 | - | 4.95 | 64,418 |
| The Only Remaining U.S. State . . . | 0 | - | 4.93 | 65,914 |
| U.S. State Superlatives #1 | 0 | - | 4.47 | 87,617 |
| U.S. State Superlatives #2 | 0 | - | 4.53 | 40,704 |
| Top 10 Largest U.S. States by Area | 0 | - | 4.95 | 160,440 |
| Top 10 Smallest U.S. States by Area | 0 | - | 4.98 | 178,041 |
| Top 10 Poorest U.S. States by Median Income | 0 | - | 4.86 | 125,521 |
| U.S. States with the Highest Percentage of Hispanics | 0 | - | 4.85 | 69,733 |
| Top 10 Newest U.S. States | 0 | - | 4.85 | 86,518 |
| Top 10 Least Religious U.S. States | 0 | - | 4.51 | 34,382 |
| Top 10 Most-Visited U.S. States | 0 | - | 4.90 | 102,129 |
| U.S. States with the Most Immigrants | 0 | - | 4.85 | 82,764 |
| Top 10 U.S. States Where the Rent is Too Dang High | 0 | - | 4.85 | 67,845 |
| U.S. States or European Countries by Area | 0 | - | 4.95 | 96,651 |
| Top 10 Richest Countries in Europe | 0 | - | 4.90 | 150,230 |
| Biggest Trading Partners - European Union | 0 | - | 4.91 | 73,069 |
| U.S. States or European Countries by Population | 0 | - | 4.97 | 133,781 |
| Category Elimination - European Countries #1 | 0 | - | 4.90 | 90,682 |
| Countries that Bordered the USSR | 0 | - | 4.93 | 166,006 |
| Modern Day Countries of Austria-Hungary on a Map | 0 | - | 4.98 | 104,323 |
| The United States... or the United Kingdom? | 0 | - | 4.87 | 98,874 |
| Commonwealth of Nations Countries | 0 | - | 4.95 | 237,939 |
| Places Where Winston Churchill Said We Would Fight the Nazis | 0 | - | 4.57 | 14,641 |
| Prime Ministers of the UK | 0 | - | 4.95 | 441,025 |
| Top 10 Asian Countries by Coastline | 0 | - | 4.92 | 96,589 |
| Countries Bordering Iran | 0 | - | 4.83 | 95,847 |
| Countries that Border Iraq | 0 | - | 4.97 | 108,927 |
| Countries Closest to Turkey | 0 | - | 4.96 | 126,713 |
| Countries Bordering Turkey | 0 | - | 4.98 | 117,700 |
| Egypt Country Quiz | 0 | - | 4.83 | 77,794 |
| Countries Bordering Saudi Arabia | 0 | - | 4.96 | 133,414 |
| Countries Closest to Cyprus | 0 | - | 4.91 | 55,894 |
| Countries Closest to Indonesia | 0 | - | 4.97 | 104,856 |
| Countries that Beat Indonesia | 0 | - | 4.86 | 56,251 |
| Countries Closest to Vietnam | 0 | - | 4.95 | 94,236 |
| Countries Bordering Myanmar | 0 | - | 4.87 | 78,009 |
| China A-Z | 0 | - | 4.55 | 67,472 |
| Countries that Beat China | 0 | - | 4.85 | 116,398 |
| Countries that Border China | 0 | - | 4.96 | 263,831 |
| Countries that Visit Japan the Most | 0 | - | 4.93 | 77,665 |
| Most-Visited Countries by Japanese | 0 | - | 4.95 | 60,375 |
| Countries Closest to Japan | 0 | - | 4.92 | 138,979 |
| Closest Countries to North Korea | 0 | - | 4.94 | 123,069 |
