Biology HL topic (Last one got rejected)

[Amekara]

Hi everyone,

So in the break, I worked on my IA topic which was about the effect of concentration of blackcurrant squash on osmosis in cut potatoes. Initially, he accepted the topic but now he's saying that it's too simple. After doing my experiment already and being half way done, I'll have to restart. Could anyone give me some good ideas that aren't too simple and that I could propose to my teacher. This hasn't happened to my other investigations in which I am completely done already, so I was a bit shocked to hear that from my teacher. Anyways, if anyone could help I'd be very thankful, some tips would be fine as well I just need to start asap because this is a serious issue in my opinion!