A Montreal teen was determined to get to Syria and committed an armed robbery on behalf of Islamic State of Iraq and the Levant to finance his travel, the Crown said during his trial's closing arguments Tuesday.

The boy, who cannot be named because he is a minor, faces two charges: committing a robbery in association with a terrorist organization and planning to leave Canada to participate in the activities of a terrorist group abroad.

"The evidence you have before you is one that is non-contested," prosecutor Lyne Decarie told youth court Judge Dominique Wilhelmy.

The accused, now 16, did not take the stand during the trial and there were no other defence witnesses.

Voluminous prosecution evidence suggests the boy's interest in Syria's civil unrest began in 2012 and, despite his parents' best efforts, he became distant and increasingly radicalized.

The court heard the parents tried in vain to keep their son in check, limiting and monitoring his Internet activity during the summer of 2014 and hiding his Canadian passport, although the accused had stolen an Algerian passport and hidden it from them.

Sitting impassively in the prisoner's box, the boy ignored his father who waved at his son at day's end to try to get his attention.

In February 2014, he used stolen credit-card numbers from his parents to attempt to make a donation to a Lebanon-based group funding the insurgency against Bashar Assad's forces.

Using the same tactic two months later, his attempt to purchase a one-way plane ticket to Gaziantep, Turkey, failed after the bank flagged and cancelled the $2,400 purchase.

"He said one way or another, he was going to combat the regime in Syria," the father told police after his arrest later in the year.

His final attempt at getting to Syria involved robbing a convenience store while wearing a mask and armed with a knife. He escaped, but his father found the loot and his tools in his hidden backpack and called police.

"Give me the bag, I'll be out of here for good," the teen boy angrily told his father after the money -- about $2,000 -- was seized.

In the week between his father's discovery and his arrest, the boy conversed on Twitter with jihadist sympathizer Martin Couture-Rouleau, who killed a Canadian Forces soldier near Montreal last October and injured another.

There were also lengthy Twitter chats with Couture-Rouleau in the days before he ran down the two Canadian soldiers, killing Warrant Officer Patrice Vincent.

Couture-Rouleau warned him repeatedly he was under surveillance and to measure his online comments, but it didn't stop the boy from asking if he could borrow $50 for a new knife.

"He was so determined that even if it didn't work, he was ready to commit another robbery," Decarie noted.

The parents told investigators in later interviews they were fearful their son would try something rash -- with the mother mentioning that the boy disappeared for several hours during the day of the Montreal Marathon in 2014 whereas he rarely left his room.

The disappearance occurred around the time the boy's mother had found a slip of paper in his pocket later ithat contained a phone number later identified as Couture-Rouleau's cellphone.

The teen has already pleaded guilty to the October 2014 robbery, telling investigators the stolen money was "the spoils of war" given Canada's military action against ISIL.

The defence failed to persuade the judge last week to have one of the charges dismissed and will make its final arguments Wednesday.