She is best known for her character Mrs. Foggybottom, a wise-cracking society woman who wittily mocked Washington, D.C. as part of her cabaret shows and other appearances from the 70s through the mid-90s.

In 1982, she received a master's degree at Notre Dame College of Belmont, CA in Montessori education, subsequently becoming a head primary teacher.

Mrs. Foggybottom, a gossipy dowager, became a staple character in her act after the owner of the Fire Escape Lounge in Alexandria, Virginia suggested using comic chit-chat between songs to engage the audiences at this club above the former Café Lafayette.

[2] Her "Mrs. Foggybottom" character gave a humorous take on political news, and threw zingers at Capitol Hill personalities while wearing white gloves, rhinestone glasses, and a feathered hat, drinking a martini and clutching a cigarette holder.

Cushing wrote original songs for her aging Washington socialite, such as the "Water Music Minuet," which joked that "the Trickle-Down Theory [was] working at last" with mandatory drug testing under the Reagan administration.

"[8] Cushing told The Washington Post that she never revisited the accompanied version of the revue because of the death of its director, Ron O’Leary.

[3] In 1988, Mrs. Foggybottom campaigned for President as the candidate of the "Cocktail Party," declaring, "I believe that what the country needs after eight years of Ronald Reagan is a four-year happy hour."

According to Joan Cushing's website, her musical Tussaud "attempts to strip away the carnival atmosphere, and put a human face on the woman who was at the very center of one of the most turbulent and bloody periods of French history.

"[13] Madame Tussaud was born Marie Grosholtz, and she was trained by a Swiss master waxworker, Phillippe Curtius, during the French Revolution.

[14] Cushing's musical Tussaud was presented through at least four staged readings from 2000 to 2006,[15] including another opening slot at the Washington Theatre Festival in 2000.

[16] There Cushing won the Pat Murphy Sheehy New Play Fund Award, and the cast, directors and musicians were honored for their ensemble work.

[20] The idea for a musical about breast cancer came in 2009 to the play's executive producer Eileen Mitchard, who wanted to give voice to those touched by the disease.

Cushing found that returning to writing the musical after her husband passed was an experience of healing, bringing a new awareness and a feeling that she had something to say.

[20] The production's director was Kathryn Chase Bryer, who was working with Cushing at Imagination Stage on theatre for young audiences.

DC Theatre Arts reviewer Terry Byrne wrote, "…hats off to composer/lyricist Joan Cushing… I cannot summon enough praise for Cushing’s creations.

"[28] The story is about a class of uncontrollable kids at Horace B. Smedley Elementary School whose sweet teacher, Miss Nelson, stops showing up.

[31][32] Describing a production at the Manhattan Children's Theater in 2005, The New York Times reviewer Laurel Graeber said, "A gifted playwright and composer, Ms. Cushing has created a musical that will charm anyone who has ever sat in front of a schoolteacher's desk – or, for that matter, behind it.

"[33] Imagination Stage also commissioned Cushing's adaptation of author Barbara Park and illustrator Denise Brunkus’s book Junie B. Jones and a Little Monkey Business!

[36] Interviewed about her TYA playwriting process at the time by The Washington Post, Cushing commented, "I gear them to kids, but I don't write down to them.

"[37] Cushing went on to write additional TYA musicals commissioned by Imagination Stage, including Miss Nelson Has a Field Day!, Petite Rouge: A Cajun Red Riding Hood, Heidi, George & Martha: Tons of Fun and 101 Dalmatians.

[38][39] The Children's Theatre of Charlotte premiered two Cushing TYA musicals, Ella's Big Chance: a Jazz Age Cinderella in 2015, which despite its Roaring 20s costumes and jazzy dance numbers only received one run,[40] and Grace for President in 2016, which also was produced elsewhere and as recently as 2023.

"[44] According to the River Cities Reader review in April 2022 of the Circa '21 Dinner Playhouse's production, Grace delivers "important messages" about voting, using one's voice and more through fun songs and dancing and lively characters.

"[48] Joan Cushing's musicals for young audiences have been produced in theatres across the United States, and some continue to be performed today.

Her son, musician Ben Buchbinder, played a selection of his mother’s favorite songs on the piano, including “My Funny Valentine.” A mini-documentary about Joan’s many accomplishments, produced specifically for the event, was shown and viewed.

[51] For the premiere of Petite Rouge: A Cajun Red Riding Hood at Imagination Stage in 2005, Jayne Blanchard of The Washington Times wrote: “Mrs.

Foggybottom has gone zydeco… in a variation of Red Riding Hood that is as snappy as a string of cayenne peppers… You are hard pressed to keep your toes from tapping… Petite Rouge is a feast for the senses and the appetite, as Miss Cushing's adaptation revels in the sights, music and food of Cajun country.

It brims with conflict and drama, without being scary; it balances the perspectives of its zany adult and obstreperous child characters; and it revels in sly comic touches.

's Playground: 'Monkey Business' Is Pure Fun" found the musical overall to be a "pleasantly idiosyncratic romp that also addresses a serious family issue: a child's jealousy and insecurity when a sibling is born."

[56] Of that time, in 2011 Joan wrote: “Those four months were the hardest, most heartbreaking, and yet most intensely loving of our… marriage.”[20] In a 2011 interview by The Washington Post, Cushing added that after Paul’s death “my whole world just turned upside down.