Five ways to have fun this weekend.

1. Saturday is Earth Day and this year’s theme is “Environmental & Climate Literacy.” The Earth Day Network and the March for Science are co-organizing a rally and teach-in on the National Mall in Washington, D.C.

There will also be local teach-ins focused on educating communities about environmental issues and empower members to take informed civic action to protect the environment. Find out where your local events are by visiting http://www.earthday.org/

2. Opening in theaters this Friday is ” Unforgettable" (R) starring Katherine Heigl as a woman who sets out to make life difficult for her ex-husband’s new wife; for kids and families is the G-rated “Born in China,” which captures intimate moments with a panda bear and her growing cub, a young golden monkey who feels displaced by his baby sister, and a mother snow leopard struggling to raise her two cubs.

3. Sunday is National Picnic Day. Did you know that during the early 19th century a group of wealthy London citizens formed “The Picnic Society” to promote picnics as social gatherings? Host your own at a local park or even in your backyard.

4, While no one knows which day in April William Shakespeare was born, his birthday is traditionally celebrated on April 23. Replace your “you” with a” thou” or “thee” and address all your friends as “cousins,” at the very least add a “eth” to the end of your verbs.

Then “go-eth” to talklikeshakespeare.org to learn more about the poet -- such as why he’s called “the Bard” -- and even download your own Shakespeare mask.

5. It’s World Book and Copyright Day on Sunday. According to the United Nations Educational, Scientific and Cultural Organization, the day is “an opportunity to highlight the power of books to promote our vision of knowledge societies that are inclusive, pluralistic, equitable, open and participatory for all citizens.”

Celebrate by writing a note in a book saying “Happy Book Day!” leaving it on a park bench. Find other ways to mark the day on http://www.unesco.org/new/en/wbcd.