After my students have completed 4 labs on Photosynthesis and Respiration, I use this worksheet (quiz) to assess each student's level of understanding for each lab and for the simplistic chemical equations for each process. Students will have seen these graphs before during each lab.
For the 1st lab, we use Spinach leaves and the Vernier CO2 sensor and chamber, for the 2nd lab, we use Spinach leaves and the O2 sensor, for the 3rd lab, we use yeast in sugar/water solution and the CO2 sensor, and for the 4th lab, we use yeast in sugar/water solution and the O2 sensor. Of course the results are often not uniform throughout the classroom but in general we get the positive slopes and negative slopes when we are supposed to.
These labs last over the course of a few weeks so I really like to use this little assessment to go back and look at the graphs and discuss the relationship to the chemical equation for each process.
You can use it as a cooperative table group exercise or as an individual quiz.