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

Clear glass mason jar containing paper butterflies on sticks, rhinestone star wand, and windchime in the form of an angel with message reading "be at peace."

Handmade card illustrated with multi-colored crayons on light purple paper. The front features a child's illustration of an animal, perhaps a horse, with its mouth open wide in the shape of the letter C. The back features a blob outlined in brown crayon and other undecipherable imagery.

Folded card with colored-pencil illustrations. Front features illustration of tree shedding leaves. Interior features sun shining over water and the name "Sarah."

Handwritten note written on lined notebook paper reading: "Filled with grief- Prayers for peace and justice."

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: "God be with you!!! We are thinking about you and keeping you in our hearts. [Heart symbol]." The church's contact information is included on the back of the envelope.

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 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."

Card with a peace sign, Star of David, and heart illustrated in marker on the front cover. The inside contains a heartfelt message from a Jewish student at Marjory Stoneman Douglas High School in Parkland, Fl. The student articulates their motivations as follows: "I feel connected to your community in a way I cannot describe. I can only tell you to stand together, and we will stand with you as well..." Some words have faded due to water exposure at the Wilkins memorial.

White posterboard with handwritten messages on either side. The front side reads: "154 mass shootings this year alone. How many lives are worth your assault rifle?" An asterisk connects to the following sidebar: "None committed by black men, illegal aliens, or women." 154 tally marks appear above. The back reads: "Life, Liberty, and the Pursuit of Happiness."

Handwritten card from a student at Goddard Middle School in Littleton, Co. The front and back cover contains the following quote attributed to the medieval Persian poet, Rumi: "Don't grieve, anything you lose comes around in another form." The words in the quote are overlaid with red, green, and blue shading. A large Star of David enclosed by three circles appears below. The upper flap inside reads: "Just because the light stopped shining, doesn't mean we're stuck in darkness. The moon comes out, but the sun still comes up every day.

Typed copy of Professor Marc Brettler's address to his students at Duke University the Tuesday following the October 27 attack. This address was delivered by two people from Durham, North Carolina: Francis and Joanna [last names redacted].

Typed Hebrew letter from a student at Hebrew Academy, a private Jewish day school in Montreal, Quebec. Translated into English, the letter reads: "Dear Rabbi from the Tree of Life Congregation, My name is Hannah [last name redacted]. I am a student at Hebrew Academy of Montreal. I am truly sorry about what happened to your holy synagogue. I hope that this will not happen again. I give [?] all your family and loved ones of your synagogue."

Envelope containing handwritten notes from the first grade religious school class at Congregation Beth Torah in Richardson, Tx. Handwritten text on envelope reads, "Hand delivered with our deepest love and sympathy. From the first grad religious school class. Congregation Beth Torah, Richardson, Texas. May their memories be for a blessing."

White posterboard with handwritten message in colored marker. The poster features a quote from 1 Peter 4:8, reading: "Continue to show deep love for each other." The word "love" is embellished with over a dozen hearts. The word, "Trump" has been crossed out on the upper left corner on the reverse.

Post-it note with handwritten message in green marker. The message reads: "Love will always win! Don't lose hope. -Gabi Z.-"

Laminated printed sign in blue and red ink on white paper. The sign reads: "Only love can conquer hate."

Card made by a student from the George Washington University Hillel. Front cover reads: "We Are One" with an illustrated heart below. The inside reads: "The GW community sends prayers and holds your community in our hearts. We will find a way to come out stronger."