One option would be to form a series RL circuit and apply a sinusoidal voltage, vi\$v_i\$, of a given frequency, \$f\$. Then measure the phase difference between the input and output voltage. From the voltage divider equation vo/vi = jwL/(R+jwL)\$\frac{v_{o}}{v_{i}}=\frac{j\omega L}{R+j\omega L}\$ the phase difference is equal to theta = 90 - atan(wL/R)\$90^{\circ}-\arctan(\frac{\omega L}{R})\$. Thus you can solve for L. You
You can make this even simpler by varying the resistance and/or frequency of the sinusoidal source until the phase shift between input and output voltages is exactly 45 deg\$45^{\circ}\$. At this point, the reactance of the inductor is equal to the resistance. Therefore L = R/(2.pi and the inductance is given by \$L = R/(2\pi f)\$.f)