What action should a math teacher take if a father requests to see his son's grades?

The most appropriate action for the math teacher to take is to provide the father with the son's grades, as doing so upholds the principles of parental rights and engagement in the educational process. Generally, parents or legal guardians have the authority to access their child's educational records, including grades, under laws such as FERPA (Family Educational Rights and Privacy Act). This legislation is designed to protect students' privacy while also acknowledging the rights of parents to be involved in their child's education.

Providing the grades not only supports transparent communication between the school and families but also encourages parents to participate actively in their child's learning. Such involvement can lead to better academic outcomes for the student, as it allows parents to support their child based on current performance data.

The other potential actions, while they may seem plausible in different contexts, do not align with the established rights parents have regarding access to their child's educational records.