Discuss the situation. Let your child vent his frustrations and express why the bad grade is so upsetting.
Praise him for being such a conscientious student. Explain that everyone can have an off day and offer a story about a test that you failed and explain how you overcame it.
Help him prepare for future tests. Work on homework together, give review tests and ensure he gets plenty of sleep the night before an exam. Remind him to read and listen closely to instructions.
Take your child's mind of the test. Cheer him up with a hug, by watching a favorite afternoon television show or baking a batch of homemade cookies. Head to the park to play or stroll through the mall to window shop.