|Nicknames||Cheseborough, Cheesey (by Chuck, Mark and Brett) Mr. Cheeseman (by Lord Fear)|
|Affiliation||Conestoga Hills Middle School, and later Conestoga Hills High School|
|Age||"No Spring Chicken!" (possibly mid 50's)|
Horace Cheseborough or more commonly known by his title name of Mr. Cheseborough is a recurring supporting character in the television show.
A grumpy science teacher and homeroom teacher who works in Conestoga Hills Middle School and later Conestoga Hills High School, Mr. Cheseborough becomes the unsuspecting victim of the battles between the Lightning Knights and the Carnival of Doom. Mistaking the characters from the Sixth Dimension as aliens, Mr. Cheseborough becomes more and more paranoid that they are out to get him, to the point where he seems to go mentally insane. He is often turns to his student Mark Hollander for help regarding the "aliens".
Mr. Cheseborough is an aging man in his 50's or 60's, with grey hair which appears to have been brown or black when he was younger, and has a growing bald spot. Mr. Cheseborough usually wears a teacher's uniform consisting of a white lab coat, a shirt which is usually either coloured brown or checkered in design, brown trousers which are held up by a belt, a tie, and brown shoes.
He often is seen wearing various badges with phrases on them reflecting Mr. Cheseborough's egotistical personality, like one that reads "Darn, I'm good." In the second season, he wears a different outfit in the last episodes, wearing a brown tweed waistcoat and a short-sleeved white shirt. He is shown to have a tuxedo outfit, and even dresses like an aristocrat in Episode 24.
Mr. Cheseborough is initially portrayed as a stereotypical grumpy teacher. Egotistical, mean and strict, he is usually unkind towards his students and enjoys distributing detention and punishments to them. He shows annoyance by the student body's apparent lack of intelligence and often looks down on them. In early episodes, he is shown as being downright unfair towards his students, taking great pleasure in marking quizzes and sings to the stupidity of the students. However, when he comes across someone who has written an answer correctly, he marks it as incorrect as "being right for the wrong reason". He is easily stressed and agitated by his students and job, complaining that he will get a large amount of paperwork if Brett Ramirez electrocutes himself whilst visiting the town's observatory and can cancel a field trip if he decides to. He has a short temper, and is can be quite proud at times, particularly when it comes to his navy days. He is shown to be quite intelligent, knowing a lot about the subjects in his lessons.
Mr. Cheseborough's mental stability was deeply affected during his multiple encounters with the Sixth Dimension characters. After being held captured for several days by Lord Fear but his memory was slightly erased, pieces of his encounter remained in memory and he became quite paranoid that aliens were after him, believing Lord Fear and his gang, and later the Lightning Knights to be extraterrestrials. His first proper signs of madness occur when he is dragged out of the middle school by police claiming that the aliens, or Googler in the case, wanted to probe his brain. He later made multiple deals with Mark Hollander to protect him from the "aliens" in return for other offers. He is still shown to be paranoid about aliens even though he tries to hide it, but when imprisoned in the Sixth Dimension by Kilobyte and later escapes, he becomes incredibly frantic, running around The Kent Bros. Carnival like a lunatic, and the authorities condemn him as a dangerous man and a wanted fugitive.
Mr. Cheseborough is shown to be intelligent and well-educated, being both a teacher and a scientist. As such he has advanced knowledge of various subjects, including information of the universe, chemicals and electricity. He likes to compare his own knowledge to those of his students, often insulting them and takes great joy in marking their exams and quizzes, laughing at their failure to answer questions correctly. It is because of his knowledge in science that he is approached and kidnapped by Lord Fear to help him destroy Ace Lightning. Mr. Cheseborough creates a chemical formula, green in colour, which displays several abilities. Lord Fear uses the chemical to temporarily drain Ace of his powers, although this is shown to only happen once. The last time Mr. Cheseborough delivers a batch of the formula to Lord Fear, Pigface is seen holding it and drinks it, giving him an ability to fire out a projectile blast of snot from his nose, which can paralyze victims. Mr. Cheseborough has a flavour for the theatre, and can drive a car, although it is trashed by Ace when he crashes onto it from above.
- Mr. Cheseborough considers Mark to be a nuisance and a troublemaker, openly insulting his British origins and behaviour on the first day they meet, and they become enemies, although Mark takes their apparent hatred for one another less seriously than Mr. Cheseborough. He calls Mark "Mr. Hollander". Mr. Cheseborough often turns to Mark for help when dealing with the "aliens", discovering Mark has connections to them in The Rat Turns, making a deal with Mark to protect him from the aliens. In the second season, Mr. Cheseborough continues to torment Mark, whilst trying to hide his belief in aliens. He eventually goes to Mark again for help when Pigface and Dirty Rat come for him, forcing Mark to guard him as he holds an alien abduction support group meeting at the high school. He screams for Mark to save him when Kilobyte kidnaps him.
- Mr. Cheseborough's relationship with Chuck is similar to his one with Mark. He finds Chuck more of an irritation, considering him an idiot most of the time, despite Chuck being one of his more active students in class. Chuck and Mr. Cheseborough are known to have more of a friendlier relationship, constructing a robot together which Mr. Cheseborough calls a "triumph in engineering". He objects to Chuck's rebellion in school during The Rat Turns, but by the end of the second season, he has to rely on Chuck to get him out of the Sixth Dimension. He calls Chuck "Mr. Mugel".
- Mr. Cheseborough is terrified of the video game characters, particularly Lord Fear, who he sees as an alien. Being imprisoned by Lord Fear and repeatedly attacked leaves quite an impression of Mr. Cheseborough. Lord Fear refers to him as "Teacher" and later calls him "Mr. Cheeseman" whilst torturing him on a ride at the carnival. Lord Fear does appear to respect Mr. Cheseborough's knowledge but considers him nothing more than a useful tool. Staff Head is shown to be quite cruel towards Mr. Cheseborough, commenting on his stupidity and how test scores for children are going down, causing Lord Fear to shut him up.
- Mr. Cheseborough hates Dirty Rat for the time they know eachother. Whilst imprisoned in the carnival, Mr. Cheseborough is repeatedly taunted by Dirty Rat who steals his digital wristwatch and badge which he torments him with. Mr. Cheseborough angrily berates Dirty Rat, telling him he will have to answer to the teacher's union Mr. Cheseborough is part of, but it doesn't even phase Dirty Rat. The two meet again in the second season, Mr. Cheseborough showing fear at seeing Dirty Rat again.
- Duff Kent and Mr. Cheseborough know eachother by face but their relationship is quite limited. Duff advertised Cheseborough as a "Mad Scientist" exhibit when he was imprisoned at the carnival, treating him as a freak. The two later encountered one another at a psychiatrist's office, Mr. Cheseborough leaping up in horror at the sight of Duff who seems to vaguely recognise the frightened science teacher.
- Mr. Cheseborough and Mrs. Kutcher work together as facaulty members in Conestoga Hills Middle School, so are at least on talking terms with one another. Mr. Cheseborough reveals to Mrs. Kutcher that he loves her cookies, describing them as utterly irresistable. At this point, the two become a couple, although their relationship seems to end when Mr. Cheseborough becomes a high school teacher.
Little is known about Mr. Cheseborough's past. His father was alive around the time Pluto was discovered by astronomers, the observatory in Conestoga Hills used to search for more stars. Mr. Cheseborough has expressed pride in his father. At some point, Mr. Cheseborough worked in the navy and had knowledge of morse code, possibly during the Vietnam War. Presumably, he took up education after retiring from the navy.
By the time Mark meets Mr. Cheseborough, he is a bitter and grouchy teacher with little hope for his students' education. In their first class together, Mr. Cheseborough is annoyed when he catches Mark gawping out of the window, unaware Ace Lightning flew by. He berates Mark and the two become enemies from that day onwards.
Mr. Cheseborough is kidnapped by Lord Fear, Staff Head and Pigface during The Substitute in an attempt to assassinate Mark and steal his piece of the Amulet. He is locked in a cage at the carnival, and watches in horror as Lady Illusion shapeshifts into an identical copy of him. Lady Illusion puts Mark and Chuck in detention to kill them in secret. As for Mr. Cheseborough, he is treated as a carnival freakshow, tormented by Dirty Rat and scared by Lord Fear. Believing his plan will work out perfectly, Lord Fear releases Mr. Cheseborough but has Dirty Rat erase his memory via hypnotism, remarking how he doesn't want Mr. Cheseborough revisiting on a field trip. Mr. Cheseborough is later seen wandering past Mark's house, oblivious to the kidnapping.
He is shown in the next episode to be back to his old grouchy self. In Once Upon A Hero, he aids Chuck in constructing a robot, Leviathan X-L1, to win a place at a computer club. His car and briefcase are destroyed by Ace and Lord Fear during a battle, and later when Lord Fear stalks Mark.
His buried memories of the kidnapping resurface during the alien paranoia that sweeps the town after Sparx is caught on tape by Chuck. Mr. Cheseborough begins to refer to the video game characters as aliens, and constructs an alien detection device to seek out the invaders. Mark volunteers to help Mr. Cheseborough, after Chuck, now basking in his apparent celebrity status is busy. Mr. Cheseborough and Mark venture into the school, Mr. Cheseborough commenting that Mark will share detention with his grand children if he breaks the detection device. The device's noises attract an enraged Googler who destroys the machine. Mr. Cheseborough runs away screaming, but compliments Mark when he believes the boy is sacrficing himself to save mankind. He is later seen being dragged into a police van but police officers, shouting to a cameraman about how the aliens wanted his brain.
He is shown to be in therapy during Daffy Duff and is shocked when he encounters Duff Kent, who vaguely seems to recognise him. He repeatedly but unknowingly meets Lady Illusion, once when she disguises herself as Mark to ruin his life, and again when she was disguised as a psychiatrist's secretary to keep an eye on Duff.
In Episode 25, The Rat Turns, Mr. Cheseborough is granted the role of temporary principal. This drives him briefly into megalomania when he wastes all of the school's savings on surveillance equipment to spy on his students, and even slashes the budgets of the school's cafeteria, much to Mrs. Kutcher's dismay. Chuck, enraged by this, starts a rebellion against his control. Mr. Cheseborough spots Mark talking to Sparx (again Lady Illusion), and orders him and Chuck to his office. Mr. Cheseborough makes a deal with Mark - protect him from the aliens and he will surrender his control.
In the last episode of the first season, Mr. Cheseborough attends the prom and reveals to Mrs. Kutcher he adores her cookies, the two shown to become a couple and dance the night away.
Mr. Cheseborough appears in Upgrades as the homeroom teacher of Mark, Chuck, Kat and Wayne. It is revealed that he was fired from his job at the middle school for raving about aliens in class, however, thanks to his teachers' union he was reassigned to the high school as a homeroom and science teacher. He briefly talks with Mark on the first day of school and advises him to keep the alien business away from him. However, he is clearly shown to still be paranoid about aliens.
Mr. Cheseborough does not play a major role again until Bound To Fail. Lord Fear, Staff Head and Dirty Rat hide in a closet in his classroom, but Wayne alerts Mr. Cheseborough to their presence. He flees to his car only for it to be crushed by Anvil, Lord Fear once again kidnapping Mr. Cheseborough. Torturing at the carnival, Duff convinces Mr. Cheseborough that Lord Fear and co. are actually good aliens whilst the Lightning Knights are evil and convinces him to aid them in destroying Ace Lightning. Believing he will be spared if he helps, Mr. Cheseborough agrees to help.
It is revealed he spent the whole night working out a way to defeat Ace, as seen by Mark when he and other students find him asleep in class. The crazed-looking Mr. Cheseborough runs out to school's boiler room where Lord Fear awaits him, and reveals he has made Chemical XZX, which has the ability to drain Ace of his superpowers. Mark follows him and eavesdrops on the conversation, secretly calling Ace and Sparx to warn them of the new weapon. Lord Fear and Mr. Cheseborough spot him, the latter chasing Mark but loses him when he escapes to do his driving test with Mr. DeCutt.
Mr. Cheseborough later delivers a second batch of the chemical after it successfully drained Ace, but for some reason Lord Fear decides Mr. Cheseborough's usefulness has reached its end and tries to kill him but a fight between Sparx and Lady Illusion outside prevents him from doing so. At school, Mark accidentally trashes Mr. Cheseborough's lab when fighting Rotgut and Wayne is accused of doing so, landing him in detention. Mark reveals he is the perpetrator and takes the punishment instead but makes a deal with Mr. Cheseborough to protect him if he stops working with Lord Fear.
When Kilobyte plans to conquer the world, he tells Lord Fear that Mr. Cheseborough should be eliminated as a potential threat along with Rick Hummel. Both are coincidentally in the high school on a Saturday, Mr. Cheseborough hosting an alien abduction support meeting which he forces Mark to attend when he is attacked by Pigface and Dirty Rat. However, Ace crashes into the room via window after fighting Kilobyte causing Mr. Cheseborough and the other group members to flee. Lord Fear chases Mr. Cheseborough, who is captured by Kilobyte and literally dragged back to the carnival.
In the final episode, Mr. Cheseborough and later Rick are imprisoned in the Sixth Dimension. Chuck watches over the two, Mr. Cheseborough successfully being freed from the video game world and materialises in the Haunted House. However, now totally paranoid and terrified, Mr. Cheseborough runs about the carnival screaming hysterically about the end of the world, etc. However, the chaos is also because of the rampaging villains. The authorities Mr. Cheseborough as the sole cause of the madness and label him as a madman.