Vocabulary :

• A leap year (or intercalary or bissextile year) "is a year containing one additional day (or, in the case of lunisolar calendars, a month) in order to keep the calendar year synchronized with the astronomical or seasonal year.[1] ... A year that is not a leap year is called a common year."
  (Wikipedia)

• February 29, "known as a leap day in the Gregorian calendar, is a date that occurs in most years that are evenly divisible by 4, such as 2004, 2008, 2012 and 2016. Years that are evenly divisible by 100 do not contain a leap day, with the exception of years that are evenly divisible by 400, which do contain a leap day; thus 1900 did not contain a leap day while 2000 did. Years containing a leap day are called leap years..."
  (Wikipedia)

Facts / Traditions :

• What's special about 29 February? (BBC)

• Leap year: 2012 is a Leap Year
  "A leap year consists of 366 days, as opposed to a common year, which has 365 days..."
  When is the next Leap Day?
  Traditions and Superstitions on Leap Day 
  Leap Day Trivia
  World Events during the Leap Year 2012
  (timeanddate.com)

• Folk Traditions :
  "There is a popular tradition that a woman may propose marriage to a man on February 29. In Greece it is considered unlucky to marry on this day.[8][9] "
  (Wikipedia)

• Top 20 craziest facts about leap years
  "Everyone knows why we have leap years - to keep our calenders in sync, stupid - but here are some crazy facts about February 29 that won't make you yawn."
  (telegraph.co.uk)
  
  

• Leap year babies celebrate a birthday today (telegraph.co.uk)

Postcards :

• Leap Year Day
  "2012 is a leap year, which means that February has an extra day: 29 instead of the usual 28. And today, in case you hadn't noticed, is February 29th, also known as leap year day!
  In the British Isles, it is a tradition that women may propose marriage only on leap years.Mail Online has an interesting article some vintage postcards relating to this custom..."
  + COMMENT + VOCABULARY + LINKS
  (englishblog.com)
  
  

• The Maiden's Vow in 1908 (img.wikinut.com)
  
  

INTERACTIVE activities :

• Leap Year Quiz (BBC)

Lesson plans :

• 10 Activities for Learning About Leap Year and Other Calendar Oddities (learning.blogs.nytimes.com)

Cartoons :

• Leap Year Cartoons and Comics (cartoonstock.com)

Cinema :

• Leap Year "is a 2010 American romantic comedy film directed by Anand Tucker and starring Amy Adams and Matthew Goode. The film is about a woman who heads to Ireland to force her boyfriend to accept her wedding proposal on leap day, when Irish tradition holds that men cannot refuse a woman's proposal for marriage. Her plans are interrupted, however, when she hires a handsome innkeeper to take her to her boyfriend in Dublin. The film premiered in New York City on January 6, 2010.[3] ..."
  (Wikipedia)