Consider life's precious verities:

-The letter "E" and the number "3."-The virtue of a bath.

-The principle of loving, or at least putting up with, your neighbor.

And give a grateful nod to another grand constant, "Sesame Street," an evergreen cityscape beginning its 25th season this week on PBS.

Be advised: You'll find many changes in the 'hood.

New Muppet characters include Zoe, a little girl monster, and the Squirrelles, a trio of female squirrels who sing Motown. Among several new human cast members is Ruth Buzzi ("Laugh-In"), who, as Ruthie, runs the thrift shop.

A new stretch of Sesame Street-life will be introduced, with such amenities as a Muppet hotel (The Furry Arms), a subway stop (the 1, 2, A and B lines), a dance studio and a park.

" `Sesame Street' has been on the air for 24 years and people are used to it," says supervising producer-director Lisa Simon, who joined the series at its inception as a baby sitter for the kid castmembers. "This will shake things up a little bit. We want to keep our edge."

But "Sesame Street's" fundamentals remain as steadfast as the long-familiar block that includes the brownstone apartment house and Mr. Hooper's grocery.

Thanks to the sense of place conveyed by that original set, along with the silly but purposeful cartoon snippets, the multiracial cast, and the rest of the inspired formula cooked up at the Children's Television Workshop, "Sesame Street" was a magic address from day one (Nov. 10, 1969).

At the top of that first show, Gordon, a young black man, tells a little girl named Sally, "You've NEVER seen a street like Sesame Street. Everything happens here. You're gonna love it!"

Fast-forward 24 years ... five-plus generations of 2- to 5-year-old devotees ... 51 Emmy Awards. And Gordon (though played by a different actor) is still a happy resident.

"Street Street" is a dazzling success story, all the more so since there's no end in sight.

But along with the kudos, this "Street" has gotten the occasional pounding.

Criticism centers on the hyperactive pace and seemingly scattershot format, which detractors feel gives pre-schoolers a distorted picture of what formal education will be like.

In his book "Amusing Ourselves to Death," Neil Postman charged that "Sesame Street" "does not encourage children to love school or anything about school. It encourages them to love television."

Maybe Postman doesn't see the forest for the T-R-E-E-S. Despite the video razzmatazz, "Sesame Street" gives top priority to something far more typical of a quality classroom than most TV shows: the careful and deliberate building of connections between seemingly isolated ideas, to form a broad span called wisdom.

For instance, awareness of your body is explored this week in a spot about elbows. This connects naturally with a lesson in hygiene: the role of your elbow in the act of brushing your teeth.

A piece about combing your hair takes an appreciative look at the differences in hair on different people - and on different animals, too.

"We want to present all kinds of different people and different ideas in such a way that children learn that different doesn't mean scary," says executive producer Michael Loman.