Maths is included to some extent in some of the CORE programs, however, by grade 3, I suggest you choose a more structured approach to support this.
Simply Homeschool includes several options:
Maths for Kindergarten through to Maths for Year 4 are Core Programs. We are working towards having Core Programs for Maths available for each school year.
Life of Fred (Grades 2-7) is available in Just Good Books
SAP Learning Maths (Grades 1-6) are in Just Good Books. This series is a Singapore Maths series which is very clear and also economical. The levels are quite challenging and in general, we suggest you will need the grade below your child's normal year.
For maths above this level, we suggest:
ICE-EM Cambridge (Yr 5-Yr 10) This is a textbook series
Maths Online (All Grades) is available with a 50% Discount through our Resource Shop.
Khan Academy FREE
Select appropriate maths for your children. Add this to your list.