concerned for ADHD son and the possibility of having a LD

I have a 9 year old son that was diagnosed with ADHD a couple years ago. We met with his third grade teacher at the beginning of the school year just like we have every year and explined that he had ADHD. My husband and I spoke with the teacher about the problems that we had noticed in the previous year and the teacher assured us that she had kids herself that had ADHD and she understood our frustration and our concerns. We noticed a trend from our son talking about how this teacher was out of school it seemed more than she was in class and so he had a subsitute the majority of the time. This concerned us because we knew that he needed consistancy when it come to the classroom. We recently met with the guidence counselor, principal, and our son’s teacher and they tell us that they was going to start giving him extra help in the classroom for about 30 mins a day. Then we would meet back in 3 weeks and see if that had helped him and if not then we would take him out of class for 30 mins, then 3 weeks later if this didn’t work then he would be taken out of class for 1 hour and then finally 9 weeks into this “intervention” and “helping him” they said then and only then could we get him tested for learning disabilities. I have voiced my concern that he has a learning diability and to get him tested but the school tells me that we have to go through these steps. I am concerned because over half the year will have gone by before they even consider testing him for any LDs. As it is right now he is in danger of failing 3rd grade. I can see him getting frustrated with everything. We are having trouble getting him to turn in his work he says “I forgot to turn it in.” when we asked him about it. I am afraid that he is “falling through the cracks” and I am trying to help him as much as I can with his homework and other things for school. I was wondering does anyone know is there a way I can get him tested for LDs on my own or do I have to wait like the school is saying? I don’t know where to turn to help with this. The teacher doesn’t seem to be helping with the situation when we approach her with questions about helping him to become better with his homework planner her response is “He is in third grade now.” I am just frustrated with the whole situation. I know that as an adult that I have been diagnosed with ADD and I know that there are things that I struggle with and I don’t want to do what I can to keep him from having the stuggles that I have had while I am going through college. I don’t know what to do! Any advise? I would apprieciate any advice with these problems.