In Chicago, McAndrew attracted significant criticism for what detractors characterized as an autocratic leadership style, as well as national renown and praise for a number of his successes as a school administrator.

After Thompson took office as mayor in April 1927, his adversarial tact towards McAndrew led to a highly-publicized administrative hearing conducted by the Chicago Board of Education.

The board suspended McAndrew from acting as superintendent pending the result of the hearing and eventually found him guilty of various charges, but the Superior Court of Cook County would later void this ruling.

His firing was due to his refusing to certify a fraudulent diploma that falsely declared that a book publisher's son had successfully completed a course of study in botany that he had actually failed.

[9][10][15] Thereafter, McAndrew momentarily left field of education and, in July 1891, became an advertising manager and district passenger agent in Saint Paul, Minnesota, for the Great Northern Railway.

In 1912, McAndrew was recommended as a prospective candidate for the role as Superintendent of Detroit Public Schools, with former president of the University of Michigan James Burrill Angell supporting his candidacy.

[13] Detroit's Board of Education voted 10–8 on July 18, 1912 to select McAndrew as their superintendent, ousting fifteen-year incumbent W. C. Martindale from his post in a single round of balloting.

[33] The Detroit Free Press wrote, There is practically nothing in the job the should appeal to a person holding the positions and drawing the salaries which are McAndrew's as long as he remains in New York, and there are, on the other hand, many features of the local situation which ought to repel him.

"[46] McAndrew also served on the advisory board of The School Review an academic journal dedicated to the subject of secondary education published by the University of Chicago.

When the question was asked with options limited to eight well-known associate superintendents of the New York City Public Schools, McAndrew was the choice of a majority of the respondents, with 39 votes.

[1][55][57] McAndrew was elected to a four-year tenure with the annual salary of the superintendent newly raised from $12,000 to $15,000, making him, perhaps, the highest-paid educator in the United States at the time.

[65] Influenced by the theory of scientific management, early into his tenure, McAndrew implemented a series of changes that made the school system run with greater efficiency.

[60][70][71] McAndrew stressed the importance of business efficiency, imposing greater supervision over teachers, including fixed criteria which did not make any variances for the size of classrooms or the backgrounds of the pupils.

[88] On April 28, 1927, the board unanimously passed a resolution petitioning the Chicago City Council to create a public referendum for approval of such a tax increase.

[93] The state legislature passed the bill, but the clerk of the Illinois House of Representatives refused to send it to the governor due to a disputed technicality, so it did not become a law at the time.

It was signed into law by Governor Len Small, and took effect on July 1, 1926, which meant that the Chicago Public Schools only had to rehire those under the age of 75 after the Supreme Court's ruling.

[100] The new bureau was responsible for drawing attendance boundaries, choosing sites for schools, recommending new structures and additions, and providing research on different aspects of educational facilities.

[102] The Chicago Board of Education established a committee in 1923 to study the feasibility of using the junior high school model in the city, eventually approving and adopting it in 1924.

On March 28, 1927, The New York Times wrote that, No work of Mayor Dever's Administration has been more praiseworthy than the improvement and extension of the public school system, the seat of enormous mismanagement and inefficiency under Thompsonism.

[111][112] The Chicago political machine was also frequently in opposition to McAndrew, and within just months of the beginning of his tenure, some demanded he resign, but the Board of Education continued to support him.

[115][116] In a surprise move, Mayor Dever broke his neutrality amid a school board dispute and on December 5, 1926, he sided with Brieske by saying that it would be preferable to see McAndrew replaced with a new superintendent.

[119][120][121][122][123] During his successful 1927 campaign against incumbent Democratic mayor William Emmett Dever, Republican nominee William Hale Thompson alleged that McAndrew was a British agent sent by King George as part of a grand conspiracy to manipulate the minds of American children, setting the groundwork for the UK to repossess the U.S. Thompson also accused the "left-handed Irishman" Dever of being part of the plot.

However, Alderman William D. Meyering, a decorated veteran of World War I, agreed with McAndrew's statement, and his support put an end to Coughlin's proposed ordinance.

McAndrew responded to the query, listing the members of the board that voted in favor of his appointment, and provided a greater description of the circumstances of the out of context quote being used against him.

[134] By July, Coath escalated the attacks against McAndrew, calling him a "bunk shooting educator" and promising that he would oust him as superintendent before the start of the new school year in September.

[9][69][138] The administrative hearing attracted national attention from the media and was treated as a ridiculous example of Chicago's messy politics and a spectacle comparable to the Scopes Trial.

[9][69][144] Time magazine characterized the Chicago Board of Education as, "a partial set of false teeth in Mayor William Hale Thompson's capable mouth", writing that they had, "orders to chew up Superintendent McAndrew".

[69][146] In December 1929, less than two years after the original administrative hearings against McAndrew began, Judge Hugo Pam of the Superior Court of Cook County voided the decision by the Board of Education.

[9][69][138] Pam ruled that McAndrew was not insubordinate, and that the school board lacked the authority to hear the case for charges stemming from the allegations of pro-British propaganda, describing them as "improper".

[114] A 1988 article published in the Chicago Tribune observed, McAndrew generally is remembered not as an autocrat but a reform-minded superintendent "persecuted" by Big Bill Thompson, who forced his dismissal in 1928 after a show trial.