Yes. You can set a format string in the Context that tells MathObjects how to format its Real numbers. See
http://webwork.maa.org/wiki/Modifying_Contexts_(advanced)#Number_Formats
for details. It is essentially an
sprint() format string, with the default being %g, which uses scientific notation when the magnitude is sufficiently big or sufficiently small, but you can change it to a "%f"-style format instead to prevent scientific notation.You might also want to consider the contextScientificNotation.pl macro file, which implements a Context designed for requiring student answers in scientific notation. It has some handy controls for the number of digits in input and output.