Wednesday:

Driscoll Bridge-Tap water vs. bottled water demonstration. Window gardening, seed sharing. Bring a reuseable container to plant a seed in. Dining halls- All day, trayless dining.

Denver parks- 1 p.m. to 5 p.m., tree planting. To sign up and volunteer, contact Jessie Burley at jburley04@yahoo.com.

Observatory Park- 9 p.m., star-gazing and night bike ride.

Saturday:City Park- 8 a.m. to noon, tree planting. To participate, e-mail Emily Susanin at esusanin@du.edu.