Hi Irene,
You will be able to find the practice sheets in the resources section after each lesson. If you are having trouble finding these PDFs, you can directly download the rich text pdf workbooks from this link – ofpad.com/mathexercises. If you open these PDFs using the free software Adobe PDF reader you can directly enter the answers in the PDF without having to print them out. You can download Adobe PDF reader from this link – https://get.adobe.com/reader/
Let me know if you need any further assistance downloading the workbooks.
Warm Regards,
Abhishek