Your aim should be to make math fun for your child and help them gain a solid understanding of the basics. Encourage your child to incorporate math into their daily activities, help them do mathematics worksheets, and then use the lessons therein to create fun activities for your child. The secret to learning math is to have an open mind about it. Just because you hated math doesn't mean your child should, and you will be doing them a disservice if you pass your negative feelings on to them. Make learning math fun, get a comprehensive set of mathematics worksheets to make it exciting and stimulating, and encourage your child's efforts all the way. Every math genius had to start with 1 + 1, just like your child.
Each grade act as a step in the whole staircase to the mathematics high_rise building. Performing poor in math in any grade is like breaking some steps in the whole staircase. As broken steps make the whole staircase risky or scary to use in the future, incomplete math competencies in lower grades make math very hard in the high school. So, what it takes to be smart in mathematics? My answer is; stay focused on math in each and every level of your studies. Participate in your class math practice sessions. Ask your teacher lots of questions until you are not clear about any concept. Mathematics is a subject of solving the problems on paper by hand rather than only to read them. As in case of Social Studies taking more readings make you smart, in math practicing lots of problems and solving them by hand makes you smart. To practice mathematics, math workbooks are the good source. You learn a concept in a workbook, then in the same booklet there are more problems on the same concept for practice. Another good method to practice mathematical concepts is using math worksheets and you can print math worksheets free of charge from the web.