As a teacher of any special needs student you are legally bound to adapt materials instruction based upon the agreement in the student's IEP. Below are documents and tips to easy adaptation that are helpful to the student and easy on you.
Instruction to Adapting Materials & Activities (see below for document)
Adapting materials can be a painstaking process, but listed on this attachment are 16 easy ways to adapt materials related to specific areas where a student may be experiencing difficulties.
Sample Schedule for Secondary Classes (see below for document)
If you are having a hard time creating an easy way to have three different activities going on at the same time, this attachment of a sample schedule can help you understand how to have organized instruction, without you instructing everyone at once. This schedule can be modified to whatever task you are performing that class period, and can be changed to lengthen or decrease time. By keeping to a strict schedule students will more likely stay on task and understand what is expected of them.
Self-Correcting Instruction Materials (see below for document)
Self-correcting Instructional Materials are ways students can complete and check their progress without coming to you for reassurance every five minutes. This document contains a couple of examples of these types of instruments, as well as giving directions to constructing one of these simple learning modification devices. These self-guided assignments give confidence to the student and time for you focus on multiple students at once.