Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a pineapple with geometric patterns surrounded by hand illustrated hearts. The back contains a handwritten note featuring a quote from the British historian, Richard Evans, as well as the stock signature: "From your friends at West Allegheny Middle School."

Post-it note with handwritten message in black marker. The message reads: "We love you!" An illustrated heart appears in the upper right corner.

Printed tag with a photograph of Irving Younger. The tag reads: "In Memory of Irving Younger." Creasing and staining due to exposure to the elements at the Wilkins memorial.

Plastic Ziploc bag with multicolored blue, red, and yellow ribbons tied into a bow on the upper right corner. Staining and dirt due to exposure to the elements at the Wilkins memorial.

Folded card with marker illustration. Cover shows two balloons, a heart, and smiley face. Inside reads: "I hope everything gets better. I hope this never happens again. We are here for you." Signed with a heart.

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

Folded card with marker and colored pencil illustration. Cover features Star of David inside heart. Interior features illustrations of heart inside rings, two hands reaching out, and tree with name "Deliliah Lieber."

Features seven "chants," mostly taken from Hebrew scripture.

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. Signed "Jack [last name redacted] 5th grade." The inside reads: "God Loves You. We will remember you. Jack Grade 5."

White poster with inscription and drawings in fuchsia marker. Bleeding on back. Staining throughout due to exposure to the elements at the Wilkins memorial.

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.

Zine page with bubble letters and information about the emotional value of hugs. Zine page with cartoon imagery and information about the value of hugs. A young boy hugs a globe, beneath the inscription: "Embrace the world one hug at a time."

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.

Post-it note with handwritten message in black ink. The message reads: "Z"L."

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 contains messages of condolences and wishes for strength and courage. The church's contact information is included on the back of the envelope.

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.

Handmade card in watercolor on paper. The card features a hand painted illustration of various flowers , including red tulips, growing from the earth against a blue sky. The card reads in the upper center: "Stronger than hate."

Folded card on light green paper. Two circular stamped imprints visible in the center of both the right and left flaps. Pink and darker green staining throughout. Due to exposure to the elements at the Wilkins memorial, the message on this card is no longer visible.

Black and white photograph showing two young women standing before the iron gates of a synagogue. Label taped onto photograph reads, "Bess & Rose Velgich in front of Oir Chodosh 1945." Original photograph has pinked edges and dried tape.