Before we talk about cellular respiration in general biology (and after we do photosynthesis), I throw the cellular respiration equation at the students and make them interpret it (in a guided manner). I lead them to determine the inputs and outputs, count the number of atoms on each side of the equation, and draw a person AND a plant to mark how the inputs get in to each organism and how the outputs get out. They are also forced to think about how cell respiration connects to photosynthesis (the goal is to get them to see that the two equations are reverses of each other). Students make a big poster with groups (my students are grouped in 4's) following the instructions on the sheet.
My students come in with basically no chemistry background, so I also use this--with the photosynthesis table poster--to help students see how equations are balanced (they don't balance it themselves, but quickly realize that the amount of matter on each side is equal), understanding inputs/outputs (NGSS terminology that fits nicely with future modeling activities you may use), identifying atoms and molecules, and just learning how to interpret "scary" information that's not so scary after all!
This activity goes so well in my classes--I would never go into explaining cellular respiration without it!
Look for my related products:
*"Photosynthesis Respiration Preparation Table Posters," which I use a couple days after this one.
*The bundle of this table poster + the Photosynthesis Preparation Table Poster at a discounted price