From the other side of the fence...
As a hearing student who is doing the opposite, taking sign language classes from hearing and Deaf teachers, I too have experienced how a hearing teacher can restrict her students!
I took an ASL I class with a Hearing instructor, the head honcho of the Speech, Language, and Communications department, and let me tell you, not only did I NOT learn American Sign Language, but I came away afraid to even try signing with Deaf people!
The way she described the culture made Deaf sound arrogant, bossy, and as if they'd bite my head off if I even tried signing with them; luckily, I failed the class (extremely unusual for me since otherwise I maintain a 3.8 GPA) and then retook it with a Deaf professor. Not only was I completely incapable of signing with her at the beginning, half the signs I DID remember were wrong. My hearing "teacher" mistook the sign for Crack Cocaine with Coca-Cola, flat out made up signs for common questions like "How" (you should have seen the look on my wonderful Deaf professor's face when I tried to ask how she was!), and would make up answers to questions that were entirely incorrect!
After taking two ASL classes with Deaf instructors, I've come to a completely different conception of Deaf culture and can actually hold a conversation now, albeit I still have to fingerspell occasionally.. But then, I'm only halfway through ASL II, so I'll get better!
Now, I want to add, this thread is of particular interest to me since I decided to change my major to English Education, and eventually will be a teacher for Deaf high schoolers, and I'm hearing. It angers me that teachers only speak in some instances and don't sign! How do Deaf children even learn efficiently, if at all?! My Deaf professors agree with me there, but.. anyway.
Not all hearing teachers are like that but most are. It is also not even the teachers' fault. It is the system....and it starts at the deaf education training programs.
I haven't started my Deaf Education training yet, since I'm still working on getting my teacher's certification as an undergrad, (and therefore don't know firsthand) but I did do some research into the master's program I'm interested in; I was SHOCKED to discover that Deaf Education was lumped in with Special Education for children with learning disabilities (like autism and such). I'll bet that's where part of the problem rears its ugly head!
I honestly don't know what else to say about this subject, but I remember all the dynamic English teachers I had in high school (who made me love the language--the written language, not the oral!) and want to give that to Deaf students too.
Literacy is the most treasured gift I have, in my humble opinion; being able to read, and read well, liberates me. Reading enables me to do whatever in life that I want, writing helps me influence whoever I want, and it absolutely breaks my heart that intelligent, capable high schoolers are graduating with 3rd grade reading levels!
Anyway.. that's my opinion, if I've made any faux pas in anything I apologize, this is my first time on this forum!