Education
5,614 pages · most loved first · page 216 of 234· Tonble one of these
Untools
A curated collection of thinking tools and mental models like decision matrices and first principles, explained with sim…
Untranslatable
A crowdsourced, Urban Dictionary-style project explaining foreign words and expressions that have no direct English tran…
Untrusted
A puzzle adventure where you escape each level by editing the game's own JavaScript, a clever way to learn code while be…
Unusual Wikipedia
A minimal page that serves up a random entry from Wikipedia's list of unusual articles with a one-line summary, and a Sh…
Unvarnished
A virtual exhibit on the history of housing discrimination in the northern and western United States from the 1890s to t…
Up-Goer Five Text Editor
A text editor inspired by the xkcd comic that only lets you use the thousand most common English words, a fun challenge…
Urban Design Group Articles
Articles from the Urban Design Group, a UK forum for architects and planners, on streets, public space and how towns and…
Urban Dictionary
A crowdsourced dictionary of slang, internet jargon, and joke definitions that has documented the evolving vocabulary of…
Urban Layers
An interactive map of Manhattan that colors every building by its construction year, letting you filter by age and watch…
UrbanRail.Net
A comprehensive reference of metro and rapid transit systems in cities worldwide, with schematic maps and technical deta…
Ursula K. Le Guin
Ursula K. Le Guin's official site, with her own blog posts and essays, interviews, a biography in her words and guides t…
US Flags Design
A set of visual design guides for every US state and territory flag, breaking down each one's history, official colors,…
US Historical Newspapers Online by State
A state-by-state guide to hundreds of digitized historical newspapers you can browse online, a handy starting point for…
US Indian Boarding School History
An overview of the US Indian boarding school system - its origins, the policies of forced assimilation, the numbers of c…
US Light Stations
An interactive map of more than 59,000 active US Coast Guard lighthouses and navigational aids, showing light characteri…
USA Mathematical Talent Search
A free monthly proof-based math competition open to any student, with years of past problem sets archived for anyone who…
USA Memory Championship
The official site of the U.S. memory sport competition, with training resources on memory palace and other evidence-base…
USACO Guide
A free collection of curated competitive programming lessons and practice problems that takes you from USACO Bronze to P…
USAFacts
A nonpartisan civic initiative making government data understandable, showing where US tax money comes from and where it…
Use The Keyboard
A clean, open source collection of keyboard shortcuts for Mac apps, Windows programs and popular websites, laid out for…
Useful Rope Knots
An illustrated guide to the most useful rope knots the average person should know, with clear photos for each knot and n…
USHistory.org
A free educational site covering American history from colonial settlement through the twentieth century in accessible n…
Using a List to Manage Executive Function
A thoughtful personal essay on a well-developed todo-list system for managing daily work when executive function is hard…
Using GPS in the Year 1565
A blog post that overlays a satellite-style track on a 1565 map to show how accurately old maps matched the real landsca…
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