Provide moral support: Children generally depend on their parents most. They rely on their parents in many aspects. They need their parents the most especially when they face some unmanageable difficulties or problems. In that case, parent's moral support works as healing mantras to them. Many failed students can again do better results by having moral support from their parents.
If you do want to produce your own worksheets and don't have the Microsoft software, you can download free tools like OpenOffice or use an online word processor or spreadsheet such as the free Google Docs which help you do similar tasks. You just need to create a table with as many rows and columns as you need and then type in some numbers before printing it off for your children to practice _ depending on the level of complexity choose single digits or multiple digits. If you're not sure what level to start at, aim low, start with easy numbers and see how your child goes, the self_esteem boost they'll get from acing the first worksheet will give them confidence for more difficult math problems.