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I'm helping my kid with a science project and realized I've forgotten the basics of how photosynthesis works. Can someone explain the main steps in a simple way, like what goes in and what comes out?

Photosynthesis is plants using sunlight to turn water and carbon dioxide into sugar and oxygen.

Inputs are sunlight, water, and carbon dioxide; outputs are glucose for the plant and oxygen for us. It mostly happens in the leaves, inside chloroplasts that hold the green pigment chlorophyll.

Two big steps, like a two part recipe. First the light dependent reactions in the thylakoid membranes soak up sunlight, split water, and release oxygen while producing ATP and NADPH. Then the Calvin cycle in the stroma uses those molecules to fix carbon dioxide into a sugar called glyceraldehyde-3-phosphate, which the plant converts to glucose or starch. The overall equation is six CO2 plus six H2O plus light energy yields C6H12O6 plus six O2. The rate depends on light, temperature, and CO2 availability, and plants regulate gas exchange through stomata to balance water loss with photosynthesis.