The Al mass was insulated to prevent too much heat from escaping.
I used a PASCO temperature probe to record the temperature change.
The blue line represented the temperature and the red line the voltage.
Temp start 20.7
Temp end 41.3
Voltage 10.1V Current 3.84A Time 600 secs
Mass 1 Kg
From this data we can work out the specific Heat Capacity of Aluminium
Energy in = Volts x Amps x Time
Energy in = 10.1.x 3.84 x 600 = 23270.3 Joules
SHC Al = Energy In / Mass x Change in temp
SHC AL = 23270.3 / 1 x 21.6 = 1077.8 J/K
Its a bit high rather than the theoretical value of 913 but then the insulationwasn't as good as it could be.