Abstract - summary of idea and result
Introduction - a short introduction that explains what citibike is and why your question is interesting. Normally this would also include a discussion of similar work previously done (a literature review) but you do not have to worry about it now.
Data - a description of the data you use and how it is processed. This should include figures (with captions!!) that help visualize and understand the data.
Methodology - a description of the methodology (test) chosen, the motivation behind it, a discussion of alternative options that were not adopted. Either this session of the next one should contain figures as well to show the results.
Conclusions - The result and its significance, including the weaknesses and strengths of the analysis. Either this session of the previous one should contain figures as well to show the results.
Each session should be between 50 and 100 words.