The strange teaching methods of a California math teacher who has been suspended over a fat-shaming quiz have been revealed on his YouTube channel. 

Tom Chan, a veteran Lowell High School teacher in San Francisco, was placed on leave after a quiz he gave his ninth-grade students included a shocking ‘fat kid’ prompt and questions about a woman’s weight, according to the San Francisco Chronicle. 

Chan has worked at the school for more than 20 years and since his ‘indefinite leave’ was revealed this week, clips from his YouTube channel have surfaced showing his bizarre teaching methods.

On the channel more than 200 videos show students how to solve Algebra I, calculus and geometry problems. 

One video, titled ‘What you need to know on the graphing calc for the AP TEST,’ features a thumbnail of him in a muscle tank, lifting a weight. 

The bulk of the five-minute clip is a screen recording of Chan using his own calculator to show how to solve the graph above. 

But the footage intermittently cuts to clips of Chan writing AP concepts on his bare and dirty feet with a green marker, apparently while sitting on his bed. 

In a series of four additional videos titled ‘Grades or Dignity,’ students are filmed performing goofy dances as a way to earn extra credit. 

Tom Chan (pictured), math teacher at a California school, is under fire for his odd teaching methods on his YouTube channel

A video called ‘what you need to know on the graphing calc for the AP TEST,’ showed Chan writing AP concepts on his bare, dirty feet, apparently while sitting on his bed (pictured)

The latest dancing video, uploaded in May 2025, carried the blunt description: ‘Kids need an A, so I provide an out.’ 

A parent told SF Chronicle: ‘They’re buying grades from him by humiliating themselves.

‘The kids look like they’re laughing and stuff, but I’m not sure all of them are into it.’

Red flags went up over Chan’s classroom content when ninth-grade Algebra 1 tests with fat-shaming and sexist questions, including asking students for their weight, were exposed.

One of the questions, unrelated to mathematics, allegedly asked: ‘How tall are you and how much do you weigh?’ followed by, ‘Pick one: Pretty or Smart. And why?’

‘I think it’s pretty inappropriate,’ Noelia Martinez, a senior at the school, told KTVU 2 News.

‘It’s not OK,’ she added. ‘I think he should take some time away from school to really think about what has happened.’

On Monday, following a complaint from an outraged parent, principal Jan Bautista made an official announcement. 

At a school like Lowell (pictured), where academic pressure is intense, concerned parents admitted that some of Chan’s teaching methods feel ‘abusive’ and ‘controlling’

The bulk of the five-minute foot video is a screen recording of Chan using a calculator to show how to solve the graph (pictured)

In her message to families, she explained that Chan ‘needed to go on leave’ with no specified return date and asked the community to respect his privacy while the school arranges coverage for his classes. 

‘We take these concerns seriously and are actively investigating,’ district spokesperson Laura Dudnick told SF Chronicle.

The February quiz, according to the outlet, featured a question seemingly about planning a Valentine’s Day date. 

The problem allegedly read: ‘The amount of money you spend on a date varies inversely to how much they weigh. A typical girl that weighs 120lbs will cost you $55.’

After being told to ‘derive the variation equation,’ students were asked to calculate how much they would expect to spend on a date ‘with Ashley, who is 220lbs.’ 

Tom Chan has taught at Lowell High School for more than 20 years, but he is now on leave after the school began investigating him after receiving complaints that his quiz questions were sexist and fat-phobic

In yet another prompt, freshmen were told to figure out how much their date would have to weigh if they only had $5 to spend on dinner. 

The controversy deepened when the outlet revealed that the test also included a question titled ‘Mr Chan vs The Fat Kid (Part 2).’

‘The fat kid from last time wouldn’t be quiet about the candy I was eating in front of him, so I punted him into the air,’ the math teacher wrote. 

Having solved problems on height and time, students were then reportedly faced with a jarring prompt about when they last ‘gave candy to a fat kid.’

The concerned parent argued that the quiz reinforced harmful stereotypes and said both families and students feared retaliation – such as grade penalties or harm to college recommendations – if they spoke up. 

Jackie Norori, parent of a Lowell High senior, told KTVU: ‘There shouldn’t be a girl’s weight based on how much a gentleman is going to spend on their date.’

She described the wording as ‘inappropriate.’

‘That, for me, is a little disrespectful,’ she added. ‘He should know better.’

Another parent, Roberto Vallejo added: ‘As a parent and having a daughter, I want to make sure my daughter is safe when I drop her off at school.’ 

He said that if the allegations turn out to be true, ‘the school has to be on top of it’ and take action. 

A parent whose older children had previously been in Chan’s classes confirmed similar experiences over the years, painting a picture of repeated troubling behavior in his classroom, according to SF Chronicle. 

They claimed Chan quizzed students on math problems they had not learned yet and scored them as part of their grades. 

At a school like Lowell, where academic pressure is intense, the parent said grading students on unknown material feels abusive and serves as a form of control. 

Lowell senior Jayden Grajeda (pictured) told NBC Bay Area News that Chan ‘has some odd mannerisms to him, but he’s a good guy’

‘I don’t think that school gives the impression they have those open lines of communication,’ the parent told the outlet, requesting anonymity.

‘I would like the classes to be told they should not let those kinds of (quiz) questions slide by,’ they added. ‘I think the school owes those classes an apology.’

However, the same parent said their teenager described Chan as one of the most well-liked teachers and believed the offensive questions were intended as ‘dad jokes’ – specifically ‘like he’s trying to be funny and it’s not funny.’

Seniors Jayden Grajeda and Ezra Medad said Chan’s class sometimes felt unusual, with certain test questions appearing ‘odd,’ according to NBC Bay Area News. 

‘He has some odd mannerisms to him, but he’s a good guy. He has kids. He just seems like a lovable kind of enjoyable teacher,’ Grajeda told the outlet.

Both boys said they were never required to watch Chan’s videos or join the dancing for extra credit, but they acknowledged that some questions could be offensive to some students. 

‘I don’t think he meant that stuff he said. He was just trying to get the kids to focus and engage with the material and actually try to learn it,’ Grajeda shared, adding that he’s looking forward to Chan returning to the classroom.

Medad also spoke positively about the 47-year-old teacher, noting that Chan took extra time to help his students succeed. 

Lowell senior Ezra Medad (pictured) told NBC Bay Area that Chan is a good teacher who ‘took extra time’ to help students succeed

Other students told KTVU that Chan used humor as a teaching method to help ease academic stress. 

‘Out of all the teachers I’ve ever had, he was the most supportive. Every day, he would tutor me after school because I was struggling,’ senior Kaela Liao told the outlet. ‘I don’t think he meant to hurt anybody by what he was doing,’ she added.

The school district has not yet outlined the timeline of its investigation or potential sanctions Chan could face.

San Francisco Unified has urged students and families to speak up about any issues, emphasizing that keeping students safe is the district’s top priority.

‘Lowell remains committed to fostering a welcoming, responsive school community where every student feels comfortable coming forward,’ the district said in a statement.

The Daily Mail has reached out to Lowell High School principal Jan Bautista, assistant principal Isaac ‘Jandro’ Alcantar, math department Chief Karl Hoffman, the school district and Chan for further comment.