Whether you prefer to wallow in nostalgia for favourite childhood books or get up to date on the next generation of children’s authors and illustrators, two new exhibitions should be just what you are looking for.

At the Laing Art Gallery in Newcastle upon Tyne, an exhibition of artwork chosen by Quentin Blake, himself a celebrated illustrator and the first Children’s Laureate, provides the viewer with examples from the work of 13 artists of varying styles. It ranges from Raymond Briggs’s earthy humour in Ug: boy genius of the stone age to Sara Fanelli’s surrealistic Dear Diary; from Michael Foreman’s evocative watercolours in War Boy to Charlotte Voake’s other-worldly The Very Best of Aesop’s Fables. Magic Pencil: children’s book illustration today will be in Newcastle all summer, with family events for the holidays, and at the British Library, London, from November.

Some of Blake’s distinctively vigorous and light-hearted drawings are on show, too. The work of all the chosen artists is thoroughly represented. In the case of Blake, there are examples from at least a dozen books, some his own - the charming, wordless Clown, for example. To Roald Dahl Blake brings a touching humanity in titles such as The BFG (Dahl sent Blake his own sandals as a reference for the giant’s footwear). Stephen Biesty’s fascinating cross-sections of everything from the human body to a man-of-war can be examined at eye level, and Tony Ross’s innocently naughty I Want My Potty can be giggled over by adults and children together.

Ross jokes that he hasn’t a particular style and that, as he works in a studio with a skylight, he’s good at rain and cloud. But his fans will know him for his sunny colours and offbeat humour in titles such as Susan Laughs (winner of the 2000 Special Needs Children’s Book Award) and The Boy Who Lost His Bellybutton; examples of both are displayed.

Posy Simmonds’s cartoon narratives, with their wicked humour and sharp social observation, are adult favourites, especially Gemma Bovery, her updated version of Madame Bovary. It looks a little out of place here, despite the inclusion of spreads from other adult-interest books such as Briggs’s When the Wind Blows. Simmonds has produced several titles specifically for children and these are represented, including Fred, about the death and funeral of a pet dog.

Blake says he hasn’t merely put together a collection of his favourites. “It’s more responsible than that - an idea of the scope of British illustration today, with examples of different styles and from different generations.”

Meanwhile, at the National Portrait Gallery, Blake is among another curator’s choices. Beatrix Potter to Harry Potter: portraits of children’s writers brings together drawings, photographs, busts, prints and paintings of more than 50 authors and illustrators from the past 100 years, as well as artefacts such as Enid Blyton’s typewriter, a Paddington Bear, and a first edition of Winnie-the-Pooh signed by A A Milne.

The exhibition, in the pipeline for five years, began when Gyles Brandreth, the television personality, journalist and former MP, was being shown round the gallery by its director, Charles Saumarez-Smith. “I told him I thought the gallery was short on popular culture and the exponents of children’s literature, both of which are important,” says Brandreth.Popular culture now has a presence in the permanent collection and in special exhibitions, and Brandreth is one of the curators of Beatrix Potter to Harry Potter.

Some of the exhibits will be familiar - A A Milne nestling by an attic window with Christopher Robin and Pooh; Beatrix looking every inch the Lake District sheep farmer, and Ted Hughes smouldering in a Cartier-Bresson portrait - but there are surprises and six new commissions. Here is Frances Hodgson Burnett, author of The Secret Garden, in Edwardian grande dame mode, and Kenneth Grahame, eyes popping like Toad’s, in a cartoon drawing. Philip Pullman lolls pensively for photographer Eamonn McCabe in the doorway of his writing cabin, and Leon Garfield, well known for his 18th-century novels and The Animated Shakespeares, photographed in 1968 smoking a pipe, looks like Sherlock Holmes.

Among the six new photographs, all by Maud Sulter, Jacqueline Wilson, crop-haired and festooned with silver chains and rings, is unforgettable. Her frank look and half-smile suggest the humanity of her popular novels; otherwise she might seem sinister. J K Rowling is here too, of course, creator of that other phenomenal Potter in the exhibition’s title, looking powerfully magical with a winged gargoyle cradled in her arms.

* Magic Pencil: related events at the Laing include master-classes, talks and family sessions. Information: 0191 2327734.Magic Pencil: children’s book illustration today, a book containing many colour plates and edited by Quentin Blake, is published to accompany the exhibition (British Council British Library pound;11.99).Beatrix Potter to Harry Potter: a full programme of talks and events includes: Childhood Rewritten, in which Julia Eccleshare, author of the book accompanying the exhibition (NPG pound;15), discusses the influence of childhood on writers, May 30, 7pm; Michael Rosen discusses his work on August 1 at 1.10pm; and Dean Hill performs Roald Dahl’s characters on August 21 at 3pm. Talks on Arthur Ransome, J M Barrie and Frank Richards and readings by well-known authors will take place throughout the summer. Tickets are required for some events. Information: 020 7306 0055.Related exhibitions: Shirley Hughes, illustrator of the Alfie and Dogger books, at the Ashmolean Museum, Oxford, September 18-January 26. Sketches, notebooks, original artwork - and the original Dogger toy. Arthur Rackham, master of the grotesque and best known for A Midsummer Night’s Dream, at the Dulwich Picture Gallery, December 18-March 2.