It’s INTERNATIONAL DARK SKY WEEK (April 13-19). The weeklong event calls attention to the negative impact of light pollution on night sky viewing. Go to the IDS Week 2015 Activity page at http://goo.gl/IehK2q.
The International Dark-Sky Association website at http://www.darksky.org/ contains information on outdoor lighting, night sky conservation, and an education section featuring lots of handouts and activity ideas.
The year 2015 is the INTERNATIONAL YEAR OF LIGHT AND LIGHT-BASED TECHNOLOGIES. The United Nations Educational, Scientific and Cultural Organization (UNESCO) sponsored website at http://www.light2015.org explores the importance of light as well as darkness around the world.
The website contains fascinating information organized into the following sections: why light matters, learn about light, hands-on involvement, cosmic light, light for development, and science stories.
Consider a school-wide STEM project centered in the school library. Focus on the need for both light and darkness for the health and happiness of people and wildlife around the world.