Hi Jamie
Your child already has an IEP, therefore, you may call an IEP meeting at any time. You are a full member of the IEP team.
In that your child is having behavior problems, you may want to consider calling an IEP meeting to address the behavior problems. A behavior plan can be included in the IEP. OR, you may want to consider requesting a Functional Behavior Assessment.
A couple of links that may be helpful regarding behavior and FBAs:
Re: FBAs, Behavior, IEP http://www.conductdisorders.com/forum/showthread.php?t=99
IDEA/IEP contains proactive measures that will help prevent discipline problems
http://www.conductdisorders.com/forum/showthread.php?t=462
There's another FBA link in the Sp Ed Archives.
Some links that may be helpful regarding evaluations:
Preparation of a Psycho-educational Evaluation Report
http://www.conductdisorders.com/forum/showthread.php?t=438
Evaluations (by school dist) and IEEs (Independent Ed evaluations)
http://www.conductdisorders.com/forum/showthread.php?t=476
School districts must evaluate in all areas of suspected disability
http://www.conductdisorders.com/forum/showthread.php?t=696