His projects often contain both animation and physical works in conversation with each other, blending analog and digital processes. A recurring theme in the physical works is an attempt to evoke aspects core to the nature of animation—like time, motion, and transformation.

Frankel’s most ambitious work to date is an opera about Robert Moses and Jane Jacobs with multi-channel animation throughout, titled A Marvelous Order (2022), created in collaboration with composer Judd Greenstein and former US Poet Laureate Tracy K. Smith.

In her review in the Wall Street Journal, opera critic and historian Heidi Waleson praised the work’s “thoughtful depiction of the conflict and its unusually imaginative multimedia form”, and called the animation “stunning”.

A Marvelous Order premiered at the Center for the Performing Arts at Penn State—the culmination of a multi-year partnership, including 3 creative development residencies. A tour is coming soon.

In conjunction with the premiere, the Palmer Museum of Art presented an exhibition of Frankel's cyanotypes, generated during his creative process for A Marvelous Order, titled "Every night we chase our shadows".

Frankel's animated films often engage deeply with music, and have been presented synchronized to live musical performances by chamber ensembles and full orchestra by institutions including BAM, the Library of Congress, Brooklyn Public Library, the San Diego Symphony, The Whitworth (Manchester), PEAK Performances (New Jersey), and New York City's River to River Festival, where his animation took over 50 video advertising screens in the Fulton Center transit hub at rush hour—synchronized to a live performance by a chamber ensemble and 5 vocalists.

Just before the pandemic, Frankel’s experimental film Emergent System (2020), created with composer Missy Mazzoli and choreographer Faye Driscoll, was commissioned by and premiered at PEAK Performances with music performed live on six(!) grand pianos, along with an exhibition of Frankel’s drawings.

Frankel’s films have been screened with recorded audio by presenters including the Film Society of Lincoln Center, the New Museum, Annecy International Animation Film Festival, Animation Block Party, EMPAC, Wassaic Project, Vimeo Staff Picks, the UN World Urban Forum, and in a shipping container in Berlin. He has received awards and fellowships from institutions including Sundance, the NEA, the Graham Foundation, the Jerome Foundation, and the Architecture Film Festival of Lund.

The profound relationships between people, architecture and urban spaces are a theme in Frankel’s work. His film, Plan Of The City (2011), created in collaboration with composer Greenstein and NOW Ensemble, was called "One of the best matches of visuals to music I've seen" by Anne Midgette of The Washington Post and "Gorgeous" by Alex Ross of The New Yorker. This work has been presented with music performed live as well as with its recorded track around the world.

Frankel was a member of the groundbreaking digital team for President Obama’s 2008 campaign, and is one of the “Superforecasters” described in the New York Times bestseller by Dr. Phil Tetlock and Dan Gardner. He has also painted over twelve thousand square feet of public murals in collaboration with his wife, artist Eve Biddle, including the recently restored Queens Is The Future (2007).