The correct answers are:
Expressing an interest in fighting alongside ISIS
Erhan was displaying signs of a fascination with extreme violence and told his teacher that when he was old enough he wanted to fight with ISIS for revenge. Erhan was feeling under threat and expressed a desire to fight for an extremist group.
Drawing symbols associated with ISIS
Adopting the use of certain symbols associated with terrorist organisations can be a cause for concern. Erhan had drawn on his hands and in his notebook his representation of an extremist group and had expressed feelings of grievance and injustice.
Watching violent videos online
Erhan was showing signs of isolation and spent a lot of time online watching extremist videos about ISIS. This is where the interest in working towards an Islamic State began, as Erhan started to build a connection with other like-minded people.
The incorrect answers are:
Not engaging with classmates
It's clear that Erhan had not settled into his new school too well and had not made many friends. However, this should not cause concern about radicalisation as there could be many reasons behind this.
Causing self-harm
Although self-harm is a serious concern for a young person's well-being, it isn't directly associated with being drawn into terrorism. In this case it's more likely an indication of frustration and insecurity and should be handled separately.