Counting in Japanese can be complicated. It is confusing to know when four is supposed to be よん or し and when seven is supposed to be しち or なな. When counting from 1-10, it seems that it doesn’t matter which one you use (strange). People usually avoid saying “shi” for 4, because it sounds like the word “death.” Superstitions in Japan is a whole ‘nother topic…
ANYWAY. I’m going to keep things simple for my kids for now and teach them how to count to ten in this manner:
1=ichi
2=ni
3=san
4=yon
5=go
6=roku
7=nana
8=hachi
9=kyu
10=jyu
In the meanwhile, I’m going to study up on larger numbers by studying this great chart from The Japan Foundation and this chart on how to count various objects/かぞえかた (also from same site) and try to use them correctly whenever I can so my kids can start hearing what correct counting sounds like. I guess it’s similar to how we have different counters like “a head of lettuce” and “a pair of pants” in English. But it seems the Japanese have a whole lot more. I think I read somewhere that there are over 600 different ways to count things!
I really like this video:
Here are more websites about counting in Japanese:
1) 数の数え方 from TAKAO-SP
2) 数え方 from Asako lida’s HomePage
3) An article on counting from ja.wikipedia.org (lots of kanji)

You are amazing! Thank you SO much. My children love going through these videos, and it’s very helpful for me to hear pronunciations! Your explanations are also very helpful for me… who would have thought there were so many ways to say one thing? I visit your site daily and have thoroughly enjoyed following your links! Very impressive!