Square card with white and yellow text against blue background. Card reads, "Mitzvah4Pittsburgh. Some spread darkness. We spread light. Choose a good deed. Choose a Mitzvah. Add light to the world," followed by four options and a place for respondents to list their name and email address. Some names and email addresses have been redacted for privacy.

Handwritten letter expressing sympathy and messages of goodwill from various lay members of the San Dieguito United Methodist Church in Encinitas, California. Last names redacted for privacy.

Post-it note with handwritten message in black marker. The message reads: "What happened here will not be forgotten." Signed with a Star of David.

Letter from a member of the Point Loma Community Presbyterian Church in San Diego, California. The letter reads: "Dear friends, My heart and prayers are with all of you as you process your loss and the events in these past few days. May God's presence and comfort be showered on every one of you. I cannot even begin to imagine... I pray for God's grace and blessings. With love, Cheryl [last name redacted]."

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a bird feather with floral and geometric motifs. The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School."

Rectangular lantern box with wood frame and glass panels. Lantern contains electric candle. Back panel is translucent and features image of a tree. Attached to the handle of the lantern is a bow and a bouquet of white lilies. Front panel features text reading, "Memories. They remind us of people and things we hold dear. They bring smiles, laughter, and sometimes tears. No matter what others may do or say, nothing will ever take these memories away. Memories are more than just a link to the past, sometimes they're all we have that will last."

Clear ribbed glass bottle with packing tape around base. Dirt and small leaf stuck to tape. Bottle contains a variety of synthetic flowers and greenery including sunflowers, oak leaves, grass, and glitter-covered poinsettias.

Letter from a member of the Point Loma Community Presbyterian Church in San Diego, California. The letter reads: "Dear Members of the Tree of Life Synagogue- My thoughts and prayers are with you as you grieve the loss of 11 of your friends, family, and members. The members of my church, Point Loma Community Presbyterian Church in San Diego, California have been praying for your congregation. We hope and pray that over time your hearts will heal and peace will enter to fill the void left by the 11. El."

Post-it note with handwritten message in black marker. The message reads: "No one ever do that."

Square card with white and yellow text against blue background. Card reads, "Mitzvah4Pittsburgh. Some spread darkness. We spread light. Choose a good deed. Choose a Mitzvah. Add light to the world," followed by four options and a place for respondents to list their name and email address. Some names and email addresses have been redacted for privacy.

Note from a member of The Church at Severn Run in Severn, Maryland. The note is enclosed in an envelope with church letterhead, reading: "The Church at Severn Run: Love Well, Live Jesus, Believe Big!" The note inside reads: "Dear friends: Praying for God's perfect peace and be with you and comfort you in this time of sorrow. Sincerely, Bob [last name redacted]. P.S. Even in this sadness, I believe God will bring good." The church's contact information is included on the back of the envelope.

Card from a congregant at the Holy Angels Parish. The front cover contains a stock illustration of a haloed dove flying in front of Noah's ark. The inside reads: "I am sorry for your loss. From: Holy Angels CCD."

Post-it note with handwritten message in blue marker. The message reads: "Together we are stronger. T and L."

Card from a congregant at the Holy Angels Parish. The front cover contains a stock illustration of a haloed dove flying in front of Noah's ark. The inside contains an illustration of a man labeled "Jesus" and reads: "I'm sorry for your family. God loves you, all day every day. We all are praying for you. And I'm sorry for your loss. We will remember your loss. We all love you. Sincerely, Nate [last name redacted]."

Card from a congregant at the Holy Angels Parish. The front cover contains a stock illustration of a haloed dove flying in front of Noah's ark. Due to water exposure at the memorial site, the message in this card has been partially erased. The remaining text reads: "[?] everybody is ok...praying for those...are hurt and kill. [Na]me: Elio age: 10... [Holy Ang]els" CCD."

Post-it note with handwritten message in green marker. The message reads: "To never be silent at the arms of our oppressors."

Card with a peacock on the front cover. The card reads: "A Catholic who loves all Jewish people! A friend, a neighbor, she loves you."

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of the word: "Smile" and other floral and geometric motifs. The back contains a handwritten note and a sticker with the words: "Stronger Than Hate" with a heart and Star of David. The stock signature: "From your friends at West Allegheny Middle School" appears in the lower center.