Jagger Strang, who was 17 at the time, was reported to police by Stafford College in September last year after he made threats to three fellow students that he planned to set off a bomb there and had numerous weapons.
At Birmingham Crown Court on Monday, he was sentenced to three years and 11 months in a young offenders' institution.
In a Snapchat discussion with one classmate that evening, he showed him a "bingo card" of mass killers, photos of homemade weapons, and videos of himself lighting substances in his garden and kitchen, and torturing cats.
The three teenagers reported him to the school the next day, which cancelled his classes and called in the police.
His home was raided on 9 September by police where they found quantities of black powder and thermite explosives.
They further discovered he had accessed instructional videos from YouTube showing how to make black powder and how to construct a detonator.
Detectives found that two days before his arrest he had researched Axel Rudakabana, the Southport killer, along with a number of other serial killers.
In addition, he had researched mass school stabbings and how to make a pressure cooker bomb.
Officers also discovered a manifesto the teenager had written in the weeks before his arrest pledging to perform a "serial killing or a rampage" and detailing a fascination with killing patients in a hospital with a knife.
The boy wrote that it was his "dream" to be famous like mass murderers such as Peyton Gendron, who killed 10 people in a racist shooting spree at a supermarket in Buffalo, New York, and Adam Lanza, responsible for the shooting of children at Sandy Hook Elementary School.
Strang's mother told police that her son had been a "nice kid, bubbly" during his upbringing in South Africa but had "completely changed" after the family moved to Britain when he was 13.
In February 2025 his father suffered a serious stroke, which left him disabled, and in August the mother moved out of the family home, following an incident with her husband.
Strang, from Staffordshire, pleaded guilty to two charges of possessing an explosive substance between 28 September 2024 and 10 September 2025.
He also pleaded guilty to two charges of possessing terrorist bomb-making videos, making threats to kill peers at Stafford College, and threatening to set off a bomb at Stafford College.
He admitted a final charge that he had been in possession of an offensive weapon, namely a blowpipe, in a private place.
He denied two charges of intending to endanger life on the basis that he had no intention of constructing a bomb and Matthew Brook KC, prosecuting, said the prosecution would not pursue them.
Detective Inspector Dave Rowlands said: "This was a deeply concerning case involving threats that understandably caused significant alarm to the students that Strang talked to and staff at the college."
'Watch what your kids do online'
Strang's mother said he spent his time in his bedroom on his Playstation console and a VR headset.
She attributed his interest in weapons to an incident when their house was invaded by four men in South Africa, and had bought the bow and arrows for him that appeared in his homemade video.
The chemicals, which she also purchased, were part of an interest in science experiments, she told police, adding: "The moral of the story is watch what your kids do online."
His grandmother told the police that Strang was "retreating into his own little gaming world and would not think about anything."
It emerged that Strang had been staying up till 3am gaming and chatting online, and had done little work for his GCSEs, which led to him failing maths and being rejected for an electrical course at college.
He had become obsessed with the video game Grand Theft Auto and associated games called Righteous Slaughter and FiveM.
He also played a virtual reality game called Bonelab which featured "intense violence and realistic gore" and Dead by Daylight - a survival horror video game - along with Ink - another survival game on the Roblox platform.
Strang was also visiting a controversial website called Goresee which hosts graphic videos of real-life violence, mutilation accidents and death.
He was also said to have taken an interest in so-called "aura-farming" - a social media trend to perform cool or dramatic actions to increase social status.
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Charles Miskin KC, defending said Strang had a "personality which tended to be obsessive and whose morbid interest was captured by the wholly unregulated violence to which he exposed himself in his room."
The "proximal causes" of his threats to kill were almost certainly the departure of his mother, and his failure, "highly unsurprising in light of his night-time activity" to get good GCSE results, the barrister added.
The judge told Strang, who sat in the dock in a black short-sleeved shirt and burgundy tie, that there was a "possibility that your obsessions for explosives and serial killing would align."
"I must consider the strong need for deterrence," the judge added. "It is easier now than ever before for people with interests such as yours to find instructions for making explosives on the internet and then to buy, through the internet, the chemicals necessary for making such explosives.
"Gunpowder and thermite are not toys, they are akin to dangerous weapons. Those who act as you did must be clear that they will receive custodial sentences if they do so."
"Thanks to the vigilance of the college's students and staff, and the swift actions of our officers, we were able to intervene quickly and prevent any potential harm."
Two other teenagers who sought to copy the Southport killings have already appeared before court and pleaded guilty to possessing information useful for terrorism.
In January, McKenzie Morgan, from Cwmbran in South Wales, was sentenced to 14 months in youth detention after he sent messages on Snapchat praising Rudakubana, shared images of the killer, and attempted to buy a 15cm kitchen knife, when he was 17.
In March, a teenager from Kirkby, Merseyside, who was 16 at the time, was given a non-custodial youth rehabilitation order after collecting kitchen knives, visiting Southport, and researching a dance class as part of a plan to copy Rudakubana's killings on the anniversary of the attack.
None of the teenagers have been charged with preparing a terrorist attack and have instead faced less serious charges because attacking children is not considered an "ideological" offence, leading to calls for a change in the law to cope with "violence fixated individuals".
Rudakubana was 17 when he murdered Bebe King, six, Elsie Stancombe, seven, and Alice Aguiar, nine, in a knife attack at a Taylor Swift-themed dance class on 29 July 2024. He was later jailed for life.
