Have I failed?
First, do not think of yourself as failing even if these students don't pass. That is not helpful for anyone. Your esteem needs to be high especially if you are going to help those with low self-esteem. You are aware that something isn't working and like all good teachers you want to do something about it. There are many things that you can do, from offering discreet additional coaching to providing individual handouts. It's a lot of work but should reap rewards. Importantly, you must not make these students feel unequal. Crucially, tasks should be kept short as attention can waver. Keep the students as involved in their learning using where possible a multi-sensory approach.
Send your dilemmas to Donald Short at firstname.lastname@example.org