I think after a while teaching, I found that sometimes we just need to ignore all the stuff that can make us feel disappointed or less motivated. We just keep teaching and keep doing what we can. Even sometimes I do feel it is really difficult to handle slower learner kids when I teach some complicated mathematics formula, but I just keep teaching it to them. Even though I realise that maybe they do not get it at all yet but I just want to include them in the learning and teaching process!
One important thing that I put in my mind is that I cannot expect all of my kids will get what I teach them. Even I do not know when they will get it. Maybe the mathematics element that I teach today will only get to them in the next 10 years!
If I put so many barriers or worry, I don't think it will help me, neither will it help them. The class is mixed with high achievers, middle and lower achievers which sometimes it makes situation real difficult. The different abilities of my kids to one another is because they are at very different levels where some of them can read, some of them are struggling to understand BM, some of them still do not know numbers and there are 25 to 40 in a class! :D
I believe that when a teacher goes into the class, and has the spirit to teach and learn from the kids, they will find a way! There will always be a way!
p/s: Just do what you can do even some people not get it! :D