I don't see anything wrong with interdisciplinary questions; in fact, I rather like them. However, I'm not too much of a fan of near-identical questions that just change the age range, unless there's a specific reason to separate the age ranges.
A more specific topic to link with a different discipline (e.g. modelling cell growth with computing) would probably solve this problem—instead of asking for a list of ideas and picking the ones you want out of the 'big list', try to ask about solving a specific problem you've encountered. Presumably, the curriculum for 11- to 14-year-olds will then dictate the sort of topics you could link to CS, giving you better questions that are less similar.
What I think would work well:
Title: How can I connect the topic of cell growth to CS lessons for ages 16-17?
Body: [include specific details about what the students know about the topic, and their CS proficiency; explain the problem you're having so far]
I can't really see how your current questions would involve substantially different answers, so it might be wise to either edit those, or consider asking for them to be merged.