Care should be taken to give children worksheets that they are capable of doing. This involves understanding and monitoring the child continually, since the level of attainment of different children would often be quite different. The worksheet should challenge the child but not overwhelm her. If the worksheet is too easy or too repetitive, it may bore the child and she would not be happy. If the activity is too difficult it would frustrate her and she would not like to take up more sheets. The children should love to do the worksheets; they should not be thrust upon them. Also doing only worksheets alone repeatedly would not be very productive. You should have a range of physical games and activities as well that would reinforce the concepts learnt.
Here are a few ideas for such activities: The alphabet song: This remains a lovely way to practise the alphabet. Sing it slowly and sing it often. If you have a large alphabet chart and point out to each letter while you sing, it will be of great value. You can give all children letter cards in order (alphabet flashcards); they can hold up each letter as it is sung. Show a magazine or picture book to children. Ask them to identify all instances of the given letter in any page. Hand out letter cards to all children. Call out a letter. The child with that card has to come in front of the class and display the letter. Divide the class into two groups. Give one group letter cards. Give other group various objects. The first group will hold up a letter. The second group should hold up an object that starts with that letter.
Another thing to look out for is what the pupil will need to solve the worksheets? Does the worksheet require the use of crayons? Does it require other things like a pair of scissors, glue and so on? Before you buy worksheets, make sure to check if they have been created to suit the geographical location that you reside in. The language and usage of words differs from country to country. It is no point buying a worksheet which is designed for children in the US for children residing in India. Also see if the worksheets involve just one way of teaching or multiple ways. Do the worksheets involve short assessments? Does it have some activity built in; does it involve elements from the childs surroundings?