It wasn't about wanting to know about photosynthesis, the original question was really about the oxygen tanks. Kids very often are looking for a simple answer. Even though the real answer is far more complex.
As a Dad who helped raise 4 Daughters, (a CPA, a Triage Nurse, PHD Mech Engineer, and a Computer Forensic Expert for the FBI), teaching at home is a crucial part of parenting. Beyond offering a wide variety of materials to learn from, (we built a library of books that filled my office), and being ready to answer those oxygen tank questions, you need to show and make asking those questions and learning from them fun.
That ain't "being really good" - That's being stupidly lucky. I spent 20 years in the back of the bus, and I never had a revival on scene or in the rig. Nor did I ever meet anyone who ever made such a claim.
Quite often patients that are brought in with CPR in progress are called dead by the ER Doctor after another 20 or 30 minutes of effort or they do get a patient back and keep them going for another few days or a week or so. Only for the patient to finally die in hospital.
But, every so often someone surprises the hell out of us and actually survives and goes on to live for years. This is why we try as hard and as best we can to keep you alive. Because there is always a chance.