There are 3 levels of intervention. School action (school only), school action plus (school plus ouside agency like occupational therapist or speach therapy), and a full blown statement.
all three will have IEPs. You should have an agreed set of targets, they should be short term, measurable, achievable and reviewed in a set time, and should be for a set period of time.
So an example, X will liten for the first 3 minutes of the lesson without shouting out.
Or, X will read 3 books by half term.
It has to be something that will help your child make progress and has to be something measurable,,,,so you don't want 'Behave better'.
These should be agreed between you, your child and the SENCO.
You should have a review data where you can see if the targets have been met, and them you can move on.
The IEP should also list ways in which the teachers will hel, and stratagies that they should use. In the review this should also be looked at, and good stratgies re-inforced