Is he on a sensory diet? If the cause is hormonal, or uneven sensations in his body for whatever reason, a sensory diet might help, particularly one full of proprioceptive activities which have the quality of regulating the sensory system either way depending upon what is needed at the time.
Also, keep data on all of the antecedents. When he starts yelling, note the time of day, when he last ate, location in the room, activity that was occurring, everything you can to get a good snapshot of what was occurring at the time.
I have dealt with this behavior and in my self contained room, yelling and violence are always met with a required relaxation break. I have two relax areas, one is a sectioned off part of my classroom, the other is a separate room that is small and has literally nothing in it. The separate one has the benefit of reducing much more sensory input and de escalation usually occurs much more quickly, but the drawback is that 2 staff go with the child which can create a coverage problem in the regular classroom.
I'm a middle school self-contained teacher with a 14 year old student with autism. He has some mild cognitive impairments, but is very articulate about his emotions and used to request cool-down time and would use language to describe his frustration. Over the past 2 months, however, he has become increasingly aggressive and even physically violent, frequently yelling for no reason and for extended periods of time. This behavior occurs both at school and at home, and all typical environment causes of this behavior have been eliminated (lights, sounds, etc) since their seems to be no rhyme or reason to why or when he's yelling and becoming aggressive. My educator instincts say this is a hormonal, chemical thing that's not a result of any external factors. Has anyone seen this type behavior in adolescents with high-functioning autism and if so, how did you deal with it in the classroom?We have used the same psychiatrist for our son since Jamie was 5 (he's now 16). This man is a well-known expert in autism and related disorders. He has often spoken about "cycles of rage" that occur when a boy on the autism spectrum reaches puberty. This seems to occur in MANY of the higher functioning kids. I also understand it can occur with kids who simply have Tourette's and it is seen in boys with all kinds of neurobiological disorders. Of course, this happens with NT boy at this age, too, but NT kids have the skills to cope a bit better with surges of testosterone, the hormone of aggression. My son turned into a MONSTER during ages 12 and 13. I honestly thought we might have to put him into residential care. Our WONDERFUL psychiatrist worked carefully with our son for a year to get an optimal medication protocol for him. By age 14, our son was back to being his old, happy and well-behaved self and that's continued to be true. We also had him enrolled in a public school especially for higher functioning autistic Middle Schoolers. The WHOLE SCHOOL was on a very effective points plan for behavior modification. Certain students also had individual plans, but my son "got" the school plan within the first week and LOVED it. I would say that the meds reined in some of his worst urges but it was the BEHAVIOR PLAN that really retaught him self-control.
Since you are this boy's teacher, the medication issue is out of your hands. However, you should understand that a lot of what your seeing is biochemical. That said, a student CAN learn to control urges if an excellent behavior plan is put into place and if EVERYBODY who works with this student follows it to the letter. I can tell you that ANY punishment will be like throwing oil on a fire. Make SURE the entire plan is ONLY positive and ONLY rewards are used. Get a BCBA to come in and do a thorough Functional Behavioral Assessment and create a Positive Behavior Support Plan. You will probably need to call and IEP meeting to get this all addressed. Good luck. What you are seeing is common.