There are a many new and old special education acronyms.  For your information the following are most commonly used:

AAC Alternative Augmentative Communication      

ADA Americans with Disabilities Act

ADD Attention Deficit Discorder

ADHD Attention Deficit Hyperactivity Disorder

ADLs Activities of Daily Living

AFO Ankle Foot Orthosis

AIS Academic Intervention Services

AM Amendment

APE Adaptive Physical Education

ASL American Sign Language

AR Annual Review

ASD Autism Spectrum Disorder

AT Assistive Technology

BD Behavioral Disorder

BIP Behavioral Intervention Program

BIS Behavior Intervention Services

CA Chronological Age

CAPD Central Auditory Processing Disorder

CF Cystic Fibrosis

CFR Code of Federal Regulations

CM Case Manager

CP Cerebral Palsy

CPSE Committee on Preschool Special Education

CSE Committee on Special Education

CSPD Comprehensive System of Personnel Development

DB Deaf-Blind

DD Developmental Delay

DS Down Syndrome

DSM Diagnostic and Statistical Manual of Mental Disorders

ED Emotional Disturbance

EDGAR Education Dept. General Administrative Regulations

EI Early Intervention

EP Emergency Placement

ENL English as a New Language

ESL English as a Second Language

ESY Extended School Year

FAPE Free Appropriate Public Education

FAS Fetal Alcohol Syndrome

FBA Functional Behavioral Assessment

FERPA Family Educational Rights and Privacy Act

FOIA Freedom of Information Act

GE General Education

GT Gifted and Talented

HI Hearing Impaired

IAES Interim Alternative Educational Setting

ICT Integrated Co-Teaching

ID Intellectual Disability

IDEA Individuals with Disabilities Education Act

IEP Individualized Education Plan

IESP Individualized Educational Services Plan

IFSP Individualized Family Service Plan

IHO Impartial Hearing Officer

IR Initial Referral

IST Instructional Support Team

LD Learning Disability

LEA Local Education Agency

LEP Limited English Proficiency

LOTE Language Other Than English

LRE Least Restrictive Environment

MA Mental Age

MD Multiple Disabilities

MD Muscular Dystrophy

MDR/MRT Manifestation Determination Review/Team

OCD Obsessive-Compulsive Disorder

ODD Oppositional Defiance Disorder

OHI Other Health Impairment

OI Orthopedic Impairment

O&M Orientation & Mobility

OT Occupational Therapy

PALS Peer-Assisted Learning System

PDD Pervasive Developmental Disability 

PLEP Present Level of Educational Performance

PT Physical Therapy

PWD Preschooler With a Disability

RS Related Services

RTI Response to Intervention

§Section (as in §300.7 in IDEA)

SAS Supplementary Aids and Services

SB Spina Bifida

SC Service Coordinator

SE Special Education

SED State Education Department

SEPAC Special Education Parent Advisory Committee

SES Student Exit Summary

SI Speech Impairment

SLT Speech/Language Therapy

SSP Supplementary Support Personnel

TBI Traumatic Brain Injury

TDD Telecommunication Devices for the Deaf

TLSO Thoracic-Lumbo-Sacral-Orthosis

TS Tourette Syndrome

TTY Teletypewriter (phone system for individuals with deafness)

VI Visual Impairment