# Tony’s Take November 2023

## This month’s topics:

### Combinatorics and Cocktail Parties.

A press release from UCSD about progress in Ramsey theory was picked up by Rebecca Dyer for ScienceAlert.com with the title: “Mathematicians Crack a Century-Old Problem That’s Perfect For Your Next Party.” The mathematicians in question are Sam Mattheus (Vrije Universiteit Brussel) and Jacques Verstraete (University of California, San Diego). In their preprint, Mattheus and Verstraete write, “Ramsey Theory is an area of mathematics underpinned by the philosophy that in any large enough structure, there exists a relative large uniform substructure.” The simplest example is this question: Suppose you have $n$ points. Join every pair of 2 points by a line colored either red or blue. How large does $n$ have to be so that in any such configuration three of the points are the vertices of a red triangle or three are the vertices of a blue one? Here, the large structure is the randomly-colored $n$-vertex graph, and the uniform substructure is a monochromatic triangle.

More generally, the Ramsey number $r(s,t)$ is the smallest $n$ such that if $n$ points are joined two by two by red or blue lines, then there are at least $s$ which are joined two by two by red lines, or $t$ which are joined two by two by blue lines. In other words, $r(s,t)$ is the smallest $n$ such that a red/blue coloring of the complete graph on $n$ points must contain a complete red graph on $s$ points or a complete blue graph on $t$ points. The example we just saw was $r(3, 3)=6$. The British mathematician, philosopher and economist Frank Ramsey (some details of his short, intense life are on the University of St. Andrews website) proved in 1930 that for any $s$ and $t$ this number is finite. Finding its exact value, beyond $r(3,3)=6$, turned out to be difficult. The ones currently known are tabulated here, with their sources. They go up to $r(3,9)=36$ and $r(4,5)=25$.

### Algebra in California, cont.

We visited this topic in May, but the mathematical unrest out there continues. The Wall Street Journal Editorial Board ran California’s New Old Math (subtitle, “Parents fight to restore eighth-grade algebra in San Francisco’s public schools”) on November 12, 2023. They give the background, going back to the decision in 2014 by the San Francisco Unified School District to stop offering Algebra I in the eighth grade. As they explain it, this was done “in the name of—what else?—equity.” The theory was that separating students into more or less advanced curricular levels would widen the gap between the performance of minority students and their more socio-economically advantaged peers. They cite a March 2023 report by three Stanford researchers (one professor and two graduate students) evaluating the actual results. The WSJ editorial does not mention one of the main findings of the report, which was a sharp decrease in AP Calculus enrollment especially for Asian students.

The editorial ran in anticipation of a rally supporting a ballot measure that would restore Algebra in grade 8. The editorial concludes by stating that the rally “is an example of parents no longer blindly accepting what school boards, administrators and teachers’ unions tell them,” and that the School Board, meeting again in February, will “face the wrath of the SF Guardians” (who organized the rally) if they don’t vote for the restoration.

A personal, nuanced view of the situation was given by Julie Lynem on the news-site CalMatters: “My son’s decision to retake algebra made me rethink California’s new approach to math” (November 8, 2023). Her son had taken and passed Algebra I in eighth grade, but was dissatisfied with his understanding of the subject and opted to repeat it, so he will likely have not taken calculus when he graduates from high school next year.

That’s the subtext in the discussions about Algebra I in grade 8: calculus. For many families, AP Calculus has become an indispensable item in their children’s struggle for admission to a prestigious college. (For Asian-American parents the pressure may be even higher, as documented in this November 26, 2023 article in the Los Angeles Times.) But students who take Algebra I in grade 9 have little chance of being able to complete AP Calculus before graduating from high school.

The pressure is not an illusion. The non-profit education news site The74 posted on November 6, 2023 Even as Caltech Drops Calculus Requirement, Other Competitive Colleges Continue to Expect Hard-to-Find Course. The website BestColleges has had a page up since March, 2022: Want to Get Into Harvard? Ace Calculus, while the non-profit JustEquations put out a September, 2022 report “Calculating the Odds: Counselor Views on Math Coursetaking and College Admissions.” The executive summary notes that even when colleges explicitly drop the calculus requirement, high school counselors “have concluded, based on their own experiences, that the course is at least strongly expected at highly selective schools.” The report quotes a high school counselor: “It is deeply problematic that college admission offices—many of which are entirely unaware of how actual math content, sequencing, programs work—use calculus as a benchmark for college admission.”

Lynem’s son, now an algebra tutor, doesn’t regret going for mastery instead of what Lynem calls “the race to take calculus”. Lynem’s story reviews the recent history of mathematics education in California, including the new state-wide Mathematics Framework adopted by the California State Board of Education last July. She spoke with the Board president, Linda Darling-Hammond, and quotes her: “Math has been taught as a set of rules and procedures, rather than helping kids use the math in real-world contexts so that students can say, ‘I deeply understand what I’m doing with this, and it’s giving me answers to things I care about.'”

The controversy about Algebra I in grade 8 has nothing to do with solving and graphing equations, etc. and their appropriateness for students at this level. It arises because “Algebra I in grade 8” is seen, correctly, by many parents as the first crucial step in the process that will get their children into a prestigious college and thereby preserve or improve their standing in society.