This tool is very important and if you have a small kid and you do not have a worksheet, then its time you got yourself one or created one for your kid. There are a number of sites over the internet that offer free worksheets that are downloadable and printable for use by parents and teachers at home or at school.
If you cannot purchase a math work sheet because you think you may not have time to, then you can create on using your home computer and customize it for your kid. Doing this is easy. All you need is Microsoft word application in your computer to achieve this. Just open the word application in your computer and start a new document.