Paul Doherty of the Exploratorium introduces four techniques for viewing the sun: solar shades, #14 welding glass, pinhole projection, and optical projection. 

The American Astronomical Society, NASA, American Academy of Opthalmology, and others have released a  definitive statement on eye safety with solar viewing instructions; also in PDF flyer version.

Paul Doherty makes a projected image of the sun with a hole in cardboard and with his hands crossed.

Make your own Sun Funnel,  a telescope accessory that allows a group of people to observe a magnified image of the sun safely. 

Video introduces the Sun Funnel with emphasis on the 3D printer version.

https://youtu.be/4RGr9FcBrSM

Video is an authoritative talk about eye safety by Dr. Ralph Chou; presented at University of Toronto for 2012 transit of Venus.

http://eclipse2017.nasa.gov/safety

NASA eclipse website features eye safety under Eclipse 101.  See one-page handout How To View The Eclipse Safely.

Ken Miller shares an elegant and effective way to project an image of the sun using a simple mirror.

Two types of make-your-own projection viewers are described, a simple one costing less than $1 and a more elaborate one for under $20.   From College of Charleston.

Excerpts from my Eye Safety content for the 2012 transit of Venus, including six ways to look at the sun.  Safety for 2004 transit of Venus is at http://media.wix.com/ugd/4c0e6f_06d1e629692c4fefb1edcb06826ae4ad.pdf

Varied content features excellent maps by cartographer Michael Zeiler and education content by Charles Fulco.

Predictions for eclipses from Fred Espenak, plus the valuable Eclipse Bulletin for 2024 solar eclipse.

Thorough map includes limb profile for sites along centerline to predict Balley's Beads, as well as an elevation profile to insure the sun is above the site's horizon.

Climatology and weather predicitions for celestial events.

"A solar eclipse is one of nature’s grandest spectacles. By following these simple rules, you can safely enjoy the view and be rewarded with memories to last a lifetime."

http://www.exploratorium.edu/eclipse

The Exploratorium has short videos about eye safety and eclipse activities.

Make your own device for observing the sun safely for a group.  Includes instructions, warnings, how-to video.

Safe solar eclipse glasses, eclipse viewers and solar filters that are ISO-approved.  For a list of other reputable vendors, see https://eclipse.aas.org/resources/solar-filters. 

Simple eclipse app from Big Kid Science.  Also available for Android at https://play.google.com/store/apps/details?id=com.germinateapps.totalityapp. 

http://www.mreclipse.com/SEphoto/SEphoto.html

A guide from Mr. Eclipse himself, whose photos are on the USPS stamp with thermocrhromic ink.

An authoritative talk about eye safety by Dr. Ralph Chou; presented at University of Toronto for 2012 transit of Venus.

Many diverse resources include "8 Seconds" essay and simulated eclipse flyover of USA.

https://www.astrosociety.org/wp-content/uploads/2016/10/uitc93.pdf

Eclipse lessons for educators follow the dynamic NGSS-based approach to instruction.

Dr. Tyler Nordgren is the artist, astronomer, and night sky ambassador of the Space Art Travel Bureau.  Buy his book Sun, Moon, Earth. 

http://bit.ly/NSNEclipse

The NSN and Astronomical Society of the Pacific are creating and curating information for amateur astronomers and other informal educators to prepare communitites off the path of totality.

As only NASA can.  Spanish version at https://eclipse2017.nasa.gov/español.

Over 100 iTunes podcasts dedicated to the 2017 eclipse, by Michael Bakich.

http://americaneclipseusa.com

Artist Jay Ryan explains eclipses with clear illustrations.

Multi-cultural eclipse folktales, including 11 audio recordings and one video recording which incorporated both subtitles and ASL sign interpretation. From Lunar and Planetary Institute.
 

Page for eclipse education on Facebook.