Maths is another fundamental element of learning for your child and covers a wide range of topics, including number, shape and time.  As always, your child's class teacher should be your first port of call if you or your child are unsure of any mathematical concepts.  However, in addition to that, the following sources of information may prove useful.
Maths Glossary
Below is a link to help out when your child comes home mentioning words like partitioning, arrays and perpendicular and you need a quick reference guide.
Number and Place Value
Addition and Subtraction
Times Tables
Telling the Time