To find the volume of a cube, you can use the formula:
\[ \text{Volume} = s^3 \]
where \( s \) is the length of a side of the cube.
In this case, the side length \( s \) is 1.5 inches.
Now, calculate the volume:
\[ \text{Volume} = (1.5 , \text{in})^3 = 1.5 \times 1.5 \times 1.5 \]
First, calculate \( 1.5 \times 1.5 \):
\[ 1.5 \times 1.5 = 2.25 \]
Now, multiply this result by 1.5:
\[ 2.25 \times 1.5 = 3.375 \]
Thus, the volume of the cube is:
\[ \text{Volume} = 3.375 , \text{in}^3 \]
Rounding to the nearest thousandth, the volume is:
\[ \boxed{3.375} \]