Does anyone know what happened to Wally's friends Chester and Tooey? They are not there on the last season.

I read somewhere that they got rid of Chester because he was similar to Wally in too many ways. I guess they wanted all the characters to be different.

I think it may be true that Chester was just too much like Wally-- nice-looking, clean-cut, more serious about academics and sports than Eddie. Tooey was more idiosyncratic, and maybe he was the eccentric one who got bumped, while Eddie and Lumpy were the 2 they decided to go with (subtracting a couple of years from Lumpy from when he is first introduced).

But it could well have been just that the 2 young actors were not interested in continuing their semi-regular roles; performers usually have a plurality of endeavors they are working on... music, theater, dancing, writing... LITB may have only been a very minor and expendable thing within their 'projects.' For that matter, they may have tasted acting and show business and decided that is not their goal anyway.