By the time your child is ready for kindergarten or school, they should be able to recognize their own name and other simple written words. The sounds of each letter of the alphabet should be familiar to your child, and they should understand the principle of reading from left to right, which way to hold a book, and possibly even be starting to read three and four-letter words.
A step-by-step set of preschool worksheets will introduce new challenges to your child - skills and concepts they have not yet learnt. With your support and encouragement, your child will learn these new skills, achieve their goals, and gain confidence that will be vital when they start kindergarten or school. Starting 'big school' brings a lot of changes into a child's life, and your child needs to believe that he or she can face new challenges and cope well.
If your third grader needs help with math, there are many useful tools that can downloaded directly from the computer. Math is a subject that is best taught with visual aids, making the lessons more tangible for students.
Worksheets also, when used properly, provide both the students and parent / tutor immediate feedback as to the child's progress. This means they can be used to point out areas where the student needs further reinforcement.