This will include counting to ten, recognizing shapes and colors, being able to hold a pencil or crayon properly, and coloring in without scribbling. Basic math concepts such as recognizing patterns, understanding quantity and some simple addition and subtraction will be useful.
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.
Many online math games are designed purely for entertainment and won't do much in terms of teaching your child. While these games can be fun and engaging for third graders, you want to choose games that will practice the skills being taught in school.
Do choose worksheets that are appropriate for the child's level, since children can get discouraged easily, if they are unable to perform the activity. Well illustrated worksheets with cartoons are also more likely to appeal to children. Worksheets that use common situations children come across at home, school, in the market place etc and that use common objects known to children would be more relevant.