Super Duper® Handy Handouts® a are FREE online, informational newsletters for teachers and parents. I love these handouts for a variety of reasons. Mostly because they are short, accurate, and cover a multitude of topics. I typically will use them to help build better understanding of what a student might need to parents and teachers.

Handouts
They also have these other resources that are special education and Speech Therapist centric resources.

Age Calculator

Apps

CEUs

Handy Handouts

Response Analyzer

SLP Case History Form

Link: Other free resources 

Super Duper also sells really good materials to support teaching discrete skills sets primarily around Speech and Language impairments. I find the pragmatic (social skills) materials to be especially helpful in working with students individually and in groups.

Super Duper site