In 9th grade you learn about boolean logic in geometry and use transistors and logic gates to design a binary adder on a bread board. At the end of the year you plan traces for a PCB, have it printed professionally and solider it. 

Next year you learn how binary adders are part of the foundation of calculator math, and using a arduino or esp32 based system focus on programming the major functions and controls.  Near the end of the year you add a graphics library and start graphing. 

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