Two amazing organizations in lower Manhattan, the National 9/11 Memorial & Museum and the 9/11 Tribute Center, have made it their missions to honor the victims of the events of Setember 11, 2011 and to help keep their stories alive.

With the 11th anniversary of 9/11 coming up tomorrow, learn how you can volunteer or donate to support their work on this 9/11 National Day of Service & Remembrance, and beyond:

NATIONAL 9/11 MEMORIAL & MUSEUM: The City’s official memorial to 9/11 opened this past year with a mission to name and commemorate those who died in the attack and honor those who risked their lives to serve and save others. Focusing on the “triumph of human dignity over human depravity,” the museum, which has been delayed in opening, will deepen that mission even further. In the meantime, online exhibitions include a timeline of the recovery and relief work, and a stunning collection of oral histories (many of which are available online).

How to volunteer/support: The memorial welcomes community members as volunteers (18 and older and willing to commit 12 hours each month). Sign up to facilitate visits, escort groups around the memorial, assist people with special needs, and help visitors find 9/11 victims’ names. You can also make a donation to support the Museum & Memorial’s work here.

9/11 TRIBUTE CENTER: Around the corner from the National Memorial & Museum, this tribute center was founded by those families who lost loved ones in the attacks. The center offers guided walking tours led by 9/11 survivors, workers who assisted in the recovery, lower Manhattan residents, or family members of victims. The guides’ backgrounds ensure that tours are not only informative and memorable, but also deeply personal.

The Tribute Center also has five galleries exhibiting different aspects of the attacks, their the aftermath, and offers installations that look towards the future.

How to volunteer/support: The 9/11 Tribute Center has volunteer opportunities for those who were directly effected by September 11. They help lead walking tours and act as volunteer gallery guides. The center also offers unpaid internships for undergraduate and graduate students who want to help design and implement school programs, work with teachers on classroom based 9/11 projects, and more. You can also make a donation to support the Tribute Center’s work here.

How are you getting involved on the 9/11 National Day of Service & Remembrance? Let us know by tweeting @repairtheworld, or in the comments below.