A BMP280 pressure transducer breakout board (purple) is mounted, waiting for you to make the I2C measurement connections with jumper wires.Do not lose any of these small components! A similar connection of a CdS photocell from A4 to ground will let you measure the light level. Pin A5 is then connected to ground through a nominally 10K thermistor to form a voltage divider so the measured voltage on A5 will depend on the resistance of the thermistor, which will change with temperature. Nominally 10K resistors are connected between +3.3 and both pins A4 and A5.(Provided pin 10 is set to ground in your code with pinMode(10,OUTPUT) digitalWrite(10,0) ) The pushbutton below the Itsy Bitsy is connected between pin 10 and pin 12, so pin 12 will be grounded when the button is pushed.In 2022 you will use a better potentiometer in the with angle indicator, supplied in the lab. A 10K potentiometer is plugged into pins A0, A1, A2 for the 2021 edition.You may want to add a connection between the two red rails to have power on both sides of the board. The 3V pin is connected to the top red rail to provide 3.3 volt power from the regulator on the Itsy Bitsy.(The grey wire is tucked under the USB connector to keep it from catching on things. The G pin is connected to the bottom blue rail for ground, and the two blue rails are connected together.You may need to make the connections yourself, while the photo shows them already made, with the Itsy Bitsy located on the right:

Arduino uno blue datasheet