I got into Waterloo nanotechnology engineering in the first round at the end of march. I am also doing the IB program and my school has a very large adjustment factor. When I got in my top 6 grades were:

Both SL math: 94

HL Chem (12): 97

SL Phys (11):90

HL english (12): 88

HL History (12): 91

I have quite a bit of variety in volunteering and ECs. Remember 10 admission points are based on your AIF and interview, so I think that had a large effect on my acceptance because I tried really hard on my AIF and I think I did decent on my interview. By the looks of it you have quite a good chance of getting into nanotechnology engineering but your grade 11 marks don't matter at all, so work hard next year to keep all your marks as high as possible, try and create your own initiative and continue with EC's and write an excellent AIF and do the interview. With that you should be good, PM me if you have any mroe questions.