Do you believe you're not good at math? Various studies suggest that with motivation and good teaching strategies, anyone can succeed in math. In fact, studies have shown that students who are motivated to do well actually learn faster than students with higher IQs who are less motivated. It doesn't matter if you are at grade level, ahead or a grade level behind. The right motivation and tools will help you succeed. Just accept your starting point and move forward with the right attitude.
It's important to develop a sense of ability in a child early on, especially when it comes to mathematics. If your child does not have a strong foundation by the time they enter HS you can expect a lot of stress and anxiety (for everyone).
Forcing kids to hit the books every night however, won't necessarily result in superb math skills. Students have to want to learn - this is where the challenge lies. Parents need to find ways to motivate their children without adding pressure. Setting goals and rewarding their success is a good starting point. As they work and achieve their objectives, their confidence will grow and math will no longer be perceived as intimidating. It also may be more helpful for parents and teachers to show how math ties to real life - for instance, understanding that four $3 slices of pizza costs $12 rather than just memorizing times tables.