How much money do I have left if I buy a soda? By the end of the week, how much of my daily allowance will I be able to save if I don't?
When you're teaching your student to write, there are a whole host of worksheets online that you can use. Many of these include clipart that will help the students learn the sounds of letters and letter combinations. There are other sheets that help the student learn to write his or her numbers. It's helpful having printable worksheets for something like this, because parents often go through quite a few of these before the child masters writing the numbers or letters correctly.
Subtract 1-, 2-, or 3-digit numbers from 3- and 4-digit number with/without renaming
However for the most part, when a worksheet is needed to help drill down a procedure, standard, or lesson, its effectiveness can and will vary.