Let's count in 10s. You can count in 10s using a number line. This number line starts at 0 and ends at 90. The numbers go up in units of 10. Let's use this number line to count in 10s to work out ...

Because your child is learning to count to high numbers by now, you can practice skip counting. Start by trying to count by 10s to 100. Then try counting by fives or twos. The more you play ...