Post-it note with handwritten message in blue marker. The message reads: "May you all rest in eternal peace. God Bless [heart]."

Cut out card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a bird with a leaf in its mouth and floral and geometric motifs. The back contains a handwritten note.

Triangle-shaped card from a student at Fountain Valley School in Colorado Springs, Co. The card reads: "Dear members of Tree of Life, I am a Chinese [student] who is now studying in U.S. I am sorry about the situation that happened recently. Personally, I support you, do not be afraid! Peace be with you." Star of David in the upper center, peace sign in the bottom center.

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a turtle 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."

Folded card with colored pencil illustration. Front shows a tree in autumn with grass and falling leaves. Inside reads: "Nobody deserves to go through what you are going through. Best wishes to all. Love [heart] Beth Chai."

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.

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.

Floral tag addressed to Richard Gottfried. The tag features a white rose on the left and the stock message: "With Deepest Sympathy" in a band on the upper center.

Card made by a student from the George Washington University Hillel. Message in the upper left corner has been partially erased by water damage at the memorial site. The remaining portion reads: "And love to you community" followed by a heart symbol. The message in the bottom right reads: "Our hearts are with you- sending love your way" followed by heart symbol below.

Post-it note with handwritten message in green marker. The message reads: "Sincere condolences to all the families. Let there BE PEACE [underlined] on EARTH and Let it Begin with ME. Philomena."

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: "We are one. We will get through this together. You are not alone. [Heart]." The church's contact information is included on the back of the envelope.

Single page with typed text. Text lists order of Friday evening service, including page numbers and readings with instructions for cantor.

Copy paper with the reflexive Hebrew verb for prayer written in dark blue marker. Inscription bleeds through back.

Folded card with marker illustration. Cover reads "Stella." Interior reads, "We at Beth Chai Congregation offer our deepest condolences. Wishing full healing to the wounded and peace to those who loves the victims" with two decorative hearts and a Star of David and the name Oona [last name and other personal information redacted for privacy] Md. Back cover features a collage of balloons, cats, and stickers, and the word "LOVE."

Floral tag addressed to Cecil Rosenthal. The tag features a white rose on the left and the stock message: "With Deepest Sympathy" in a band on the upper center.

Letter from a member of the Point Loma Community Presbyterian Church in San Diego, California. The letter is dated Nov. 4, 2018 and reads: "Dear Sisters and Brothers, Please hold fast to the promise of God's power and presence in all things. While we have choices He has the final word on how our circumstances, losses, and gains will serve His kingdom. You are loved, prayed for, and supported by many in this trying and confusing time, and always. Please reach out the community of believers for any need. Thank you for your continued faith and courage, which inspires generations.

Letter from a member of the Point Loma Community Presbyterian Church in San Diego, California. The letter reads: "To the Tree of Life Community, We are praying for you in San Diego and sending you blessings through this difficult time. God is with you and holding your members who passed in His loving hand. May His light fill your hearts during these dark times and remind you of His love even through the things we cannot explain. Bless you, Gresham." An illustration of a tree filled with hearts appears below.