The Monthly Film Bulletin wrote: "The plot of
The Magnet is not allowed to develop naturally, but is carried through a whole series of improbable coincidences and misunderstandings. The attitude to children, too, is less natural than determinedly avuncular and whimsical, and Charles Frend has been unable to make William Fox (Johnny) appear very much of an actor. The same artificiality is apparent in the film's humour; the story departs from the adventures of the child to include a number of conventional jokes at the expense of such familiar targets as psychiatry, domestic difficulties, and the Labour Government. These defects and confusions in the script apart, the film might still have been knit together by strong direction.
The Magnet, however, lacks both style and unity; even the location work seems flat, and it is only in some scenes on the beach that the picture really achieves a sense of atmosphere."
The Daily Film Renter wrote: "Simple? Yes. Funny? Very. Ingenuous? Yes. Well directed? – a bit uneven maybe, but it goes with the boisterous open-air swing that made
Hue and Cry a stand-out laugh raiser. William Fox, a masculine fairheaded snip, with an air of misleading innocence, is a cinch in the role which is in the direct line of succession to the "
William" stories, though not perhaps, so clean cut. Rivalling his brilliantly natural performance is the Liverpool dead-end kid, played by Keith Robinson, whose favourite retort 'You're a Liar' gets an audience roar every time he says it. The necessary long-suffering parents are beautifully understated by Kay Walsh and Stephen Murray. The Merseyside settings are particularly effective."
Picturegoer wrote: "Ealing Studios has a definite find in William Fox, the boy who plays the lead in this slight, but wholly convincing tale about the spirited young son of a psychiatrist. ... Stephen Murray is competent as his psychiatrist father. Good support comes from the rest of the cast. Delightful, naive boyhood sequences make this a very enjoyable little picture. It drags at times, but there's always plenty of interest in young William Fox."
Picture Show wrote: "Refreshing, amusing and friendly comedy of a small boy's troubles, imaginary and real, after cheating another boy out of a coveted magnet. Delightfully acted and imaginatively directed."
Leslie Halliwell described it as a "very mild Ealing comedy, not really up to snuff". In
British Sound Films: The Studio Years 1928–1959 David Quinlan rated the film as "average", writing: "Slow picture has some charm, is finally too improbable." The
British Film Institute's reviewer criticised it as "somewhat burdened by cumbersome moralising and too many credibility-stretching coincidences and misunderstandings" and described it as "an attempt to revisit the success of Clarke's earlier
Hue and Cry". ==References==