I found a fun site today called ABCya! The creator is a public school teacher. Her games are geared for children in K-5th grade.
Here is what the site says:
ABCya.com was designed with a focus on parents, teachers and children. The services and features on the website reflect our focus.
The navigation features of the website are simple and straightforward. The homepage provides links to six main grade level categories: Kindergarten, First Grade, Second Grade, Third Grade, Fourth Grade and Fifth Grade. The grade level categories are broken down by content categories: Letters, Numbers, More (shapes, social studies, art) and Holidays.
With the guidance of an adult, children will be able to successfully navigate the website..