FOR decades now, the shenanigans of Bert and Ernie, Big Bird, the Cookie Monster and the other characters on Sesame Street have defined what good children's television is all about - educational viewing that is always entertaining. Sesame Street is so engaging many adults give it the occasional look. So if someone wants to compete, what kind of show will do the trick? STAR Plus is betting on the back-to-basics The Magic Box - a new programme taken from an old concept that has caused a buzz in the United States. Created by New Zealand child expert Wendy Pye, The Magic Box, with a minimum of fuss, teaches the alphabet and reading skills through the traditional approach to story-telling. Fine. A noble cause. But does it capture the imagination of children? Since The Magic Box is strictly for the pre-school crowd, it is necessary to consult the best professional critics available. Would a child watch this show on a daily basis? And what kind of socio-political impact could it have? ''Yes,'' said Nicholas Garthoff, aged 21/2. But can we remain content with the Garthoff judgement? As a critic, he is notoriously enthusiastic, even prone to jumping up and down with his arms flailing. A far more articulate viewpoint came from Patrick Stevens, aged 31/2. ''Yes, because I liked the bit where the people dressed up like dinosaurs.'' Dinosaurs? That is the easiest sell going these days. Dinosaurs are bigger than The Beatles were. And, when pressed, Stevens did admit to preferring Sesame Street. So it came down to Rachel Flint, aged 51/2, to put The Magic Box into some sort of intellectual perspective. ''Yes, because there are lots of stories. But I didn't learn anything - I know this already.'' Hmmm. Very contradictory. And one suspects Flint was giving the opinion she thought was expected of her - another typically obtuse critic! It proved more enlightening to simply watch the children's faces. The opening sequence to The Magic Box was laced with sophisticated computer animation - a high-tech light show which kept the children mesmerised with anticipation. After that came a series of watercolour illustrations like those in a story book, depicting the various colours a balloon can be. The balloon story was repeated several times, prompting some of the children to call out ''balloon'', ''red'' or ''bang!'' as cued by the voiceover. The straightforward content, the repetition and the interaction are crucial to The Magic Box. According to Pye, ''children love the familiar - they feel comfortable with things they know. The different parts [of the show] can be watched again and again, reinforcing in a very comfortable and natural way the learning of the other parts''. THAT may be. But by the time the second and third stories rolled around (The Three Pigs and something about a costume party), our critics had clearly become bored. Yes, The Three Pigs did have its moments (it is a classic after all), but the costume segment had allconcerned searching for their toys. On the other hand, a song about dinosaurs and a rapping run-through of the alphabet were moderate hits, triggering bopping heads and tapping feet. It was an attempt to mix sugar with medicine in the hope both would be swallowed. But why not do that consistently? Sesame Street does. Whatever, STAR Plus begins airing the 52 episodes of The Magic Box on a daily basis from tomorrow. Will it catch on? That, I'm afraid, will not be determined by anyone capable of reading - or writing - this sentence.