PBS Kids has a section with number games. There are also videos about numbers featuring characters such as Curious George, Cat in the Hat and Clifford. The games and videos are suitable for preschool children at various levels. There are games and videos that teach children to say the number sequences but also games to deepen children's understanding by letting them match and add numbers.
Fun School site has a section with activities for preschool numbers. Visit Scholastic and you will find a wide range of online games as well as articles with activities to help children learn to count.
On the website e-Learning For Kids there are addition and subtraction games. This site is a global e-learning site, and children can learn about money and their values in different countries.
The site Ideas For Preschoolers has a wide range of material that you can print out and use to teach preschool numbers. There are material that can be printed out and used in a file folder. You can print out pictures of such things as pizza pepperoni slices, flowers, snowflakes and squirrels. Ideas for how to teach numbers to preschoolers are also available on the site. On the website First School, there are fun activities dedicated to numbers. Choose from a selection of printable activities such as caterpillars or centipede number templates to online dots to dots.