You have a child with autism in your classroom who has a hard time with transitions. How do you accommodate this child?

In the UK if you were to have an autistic student in a Mainstream school you would expect them to have a Learning Support Assistant who, although not a teacher, woulld be a specialist in autisim. You would then naturally work with this LSA and take their advice on what the best teaching methods would be to employ for this particular student, you are effectively working as a team.