To find the slope of the line that contains the points \((-2, 2)\) and \((3, 4)\), we can use the formula for the slope \(m\) given by:
\[ m = \frac{y_2 - y_1}{x_2 - x_1} \]
Here, \((x_1, y_1) = (-2, 2)\) and \((x_2, y_2) = (3, 4)\).
Substituting the coordinates into the formula, we have:
\[ m = \frac{4 - 2}{3 - (-2)} \]
Calculating the numerator and denominator separately:
\[ m = \frac{2}{3 + 2} = \frac{2}{5} \]
Thus, the slope of the line that contains the points \((-2, 2)\) and \((3, 4)\) is
\[ \boxed{\frac{2}{5}}. \]