Handmade, screen-printed card on red paper with blue paint. A heart appears in the center. Signed, lower right: "Love, Brian S." The card has been laminated. A piece of clear tape appears on the back.

Post-it note with abstract illustration in red marker.

Post-it note with handwritten message in blue ink. The note features an illustration of a heart with the numbers "412" written inside.

Patch featuring logo of Pittsburgh Penguins adapted to resemble a Star of David above the words "Stronger Than Hate."

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 mourn for you loss and we pray the God of Abraham embraces you in fresh, new ways today and always! Shalom!" The church's contact information is included on the back of the envelope.

Typed letter from Amy Jonas of the Hebrew Institute of Pittsburgh to Ruth Edenstein, President of Congregation Dor Hadash, thanking Dor Hadash for sponsoring the construction of a ramp on the Hebrew Institute building.

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 your sisters and brothers and we stand with you today and every day. We love you and our prayers are with you." The church's contact information is included on the back of the envelope.

Folded card with the "Stronger Than Hate" graphic printed in black and white on the front cover. The names of the eleven victims of the October 27 attack are written inside, followed by the following promise: "Rest in peace [heart]. I promise to fight for a world where love prevails hate." An additional message appears on the back: "May we fight to ensure this NEVER happens again. Ahava (love)." It concludes with the names of the eleven victims.

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, as well as the stock signature: "From your friends at West Allegheny Middle School."

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."

Hallmark card from a member of St. Peter's Episcopal Church in Londonderry, New Hampshire. The envelope features an illustrated heart. The front cover reads: "Peace" and features a sandy landscape with a blue sky and orange flowers. The inside reads: "I pray you will find love and peace in the everyday actions of people who care for you. We send so much love to you from Londonderry, New Hampshire and beyond. Love and peace, Erin [last name redacted]."

Post-it note with handwritten message in green and red marker. The message reads: "Love is stronger than hate. Rest in peace. Jaime." The "o" in love and the dot in the "i" in Jaime are written with hearts.

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 card from a student at Goddard Middle School in Littleton, Co. The front cover contains the following quote attributed to the movie star, James Dean: "Dream as you'll live forever, live as you'll die today." A Star of David appears below. Another quote, attributed to the author, August [middle initial and last name redacted] appears on the bottom right: "An empty box in an empty room is hard to fill, but over time it fills slowly..." An open, empty box appears above.

Post-it note with handwritten message in green marker. The message reads: "May your memories be forever a blessing and may the Holy One hold in his Heart forever."

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.

Typed bilingual Hebrew and English letter from a student at Hebrew Academy, a private Jewish day school in Montreal, Quebec. In English the letter reads: "Dear Rabbi, I hope all is well. I'm talking to you from Montreal. I heard what happened last week and I want to say we have been saying Tehillim (Psalms) for you guys in Pittsburg[h]. The whole Jewish community is so sad and I want to say that we are really sorry. I hope all the injured will be okay and heal faster. Sincerely, Joshua [last name redacted]."