Diversification in a mixed ability class

Only a week ago I talked about the challenges of teaching large classes. However, I've come to realize that, in effect, it's not the number of students that is actually challenging. If one had a class of forty well-behaved students of the same age, gender, and level of proficiency, with the same interests and cultural backgrounds, it might well be much easier than teaching a group of five students who share none of the attributes. I'm well aware of the fact that I'm oversimplifying. What I'm trying to imply is that over less than a week my main focus has changed from 'large' to 'mixed ability'.

One of the groups I teach this year encompasses several reference levels as described by the CEFR (Common European Framework of Reference for Languages). I haven't actually measured it but I estimate that in the group there are 1) a couple of learners at the A2+ level - the weakest, least confident learners struggling with the core matter they need to acquire 2) quite a few at the B1 level - this level corresponds with the coursebook we're using so I suppose they feel quite comfortable 3) some at the B2 level - those who take it easy and generally get good grades, and 4) a few at the C1 level - in short, those who have answers to all my questions and nothing ever surprises them. I should stress that all the learners still have two full academic years to go to finally and officially achieve B2 level - the expected outcome of secondary education, i.e. the teacher's ultimate goal. However, if this was my only goal, some of the students could let their hair down or skip all the English classes from now on, and they would still pass their final exams. This is not what I want (the skipping).

Inevitably, I came to a conclusion that helping my students achieve the B2 level can't be my primary goal any more. I simply needed to change my mindset and start thinking about alternative approaches. I came up with a simple idea: in the next two years I'm planning to help my students to follow this pattern of development:

A2+ > B1 > B2
B1 > B2 > B2+
B2 > B2+ > C1
C1 > C1+ ? 

I don't know if this pattern makes any sense to the reader. I'm not sure whether it makes sense to me either. What I'm trying to say is that I plan to push each and every student further up towards a higher level. I'm not so worried about the first group. If the students work hard enough, they might be virtually pulled up by the demands of the teacher (and the system) but also by the presence of more proficient students. I suppose most of them are more or less externally motivated because they want to pass their exams. The students who've already achieved the B2 level may feel they don't need to work hard any more so internal motivation is the key here. I need to convince them that this is not the terminal station. The most challenging subgroup seems to be the last one. Why should they bother at all? They are at a fairly high level already and it may be difficult for me to offer something they don't know, at least within the regular classes where I need to help the less proficient students. 

Enough of theory; I'd like to share a couple of activities I've done so far, which, I believe, worked quite well for all the subgroups. When we worked on compound nouns, I handed out an extensive list of extra vocabulary items and asked Ss to highlight those they think they know. The strongest Ss highlighted 90% of the items while the weaker students were only familiar with, say, 30%. This didn't matter though. All the students subsequently worked with what they knew and shared their knowledge with each other. Eventually, they all learned more than they had known before. 

The other day we worked on reported speech. The topic of the lesson was mystery and crime. As an extra activity I handed out a short story from a level 5 graded reader and played the recording while Ss followed the text. I asked them to highlight all the direct speech chunks as they were listening. The story was quite easy for the most proficient Ss within the group. Nevertheless, it was also gripping and thus kept them in suspense all the time. I was pleased to see that the text was sufficiently challenging yet comprehensible for the weaker students. The main aim was not purely and only linguistic (apart from the focus on reported speech, which only took a couple of minutes anyway); it was a mysterious story which incited a lively discussion. Also, as the Ss could keep the texts, they could read them at home as many times as they needed. Some Ss probably had to work a little harder than others but that's just fair. The students will also need to change their mindsets, not just the teacher. 

The basic requirements are the same for all students, though. They write the same tests and there are specific criteria they need to meet in order to get a good grade. I should stress that this doesn't discriminate the weaker students. If the students work hard, they can all get decent grades, no matter what level they are; this is how the tests are designed. Surprisingly, the most proficient students are sometimes less successful because they overestimate their knowledge, or they don't find it necessary to revise for exams. So it's the diligence and the desire to improve which finally pay off, not just a natural talent, and I believe it's the way it should be.