There are also teachers who use these kinds of techniques to teach in a more animated manner. The idea is to keep children interested because without their attention, it is difficult to make them absorb what you are trying to teach.
A young child may not be able to write or read more than a few words. Worksheets should be created keeping these factors in mind. When you buy worksheets for your children, look for how the concept is explained. Is it pictorial or is it just a collection of words? A pictorial worksheet will hold the attention of a child more than just a combination of words.