Things to do for £5 or less in London this week.
All week
A MAGICAL FLORAL DISPLAY: Rebecca Louise Law has suspended 10,000 irises from the ceiling of this gallery, creating a somewhat magical environment to enjoy. NOW Gallery (Greenwich Peninsula), free, just turn up, until 7 May
SELFIES: Are selfies art now? Saatchi Gallery thinks so — it's got a whole exhibition dedicated to selfies, from painted self portraits to celebrity snaps. Saatchi Gallery (Chelsea), free, just turn up, until 31 May
THE BEST IN PHOTOGRAPHY: We always look forward to the Deutsche Borse Photography Prize as the benchmark of photography as art. The finalists' styles change dramatically every year, and this annual exhibition has included many impressive winners in the past. The Photographers' Gallery, £4 (free before noon), just turn up, until 11 June
RUBENS & REMBRANDT: The two names alone should get art fans excited. The National Gallery has a display of these two Old Masters in (the often hard to find) gallery B. Rembrandt's self-portraits are brilliant, showing a young artist on the up, and a somewhat morose old man towards the end of his years. Couple these with the bold Biblical scenes of Rubens and you're onto a winner. National Gallery, free, just turn up, until 16 July
HARRY POTTER: This extremely popular exhibition of designs and artwork from the Harry Potter films is still going on. See wizarding newspaper The Daily Prophet, 'wanted' posters, and Hogwarts textbooks, among other film props. House of MinaLima (Soho), free, just turn up, ongoing
Monday 24 April
ROMAN LONDON: Deaf and hard of hearing visitors can take a subtitled tour of Museum of London's Roman London exhibition. Museum of London, free, book ahead, 6pm
Tuesday 25 April
NEW EXHIBITION: The UK Colour Pencil Society is showcasing work by established and emerging artists. Menier Gallery (Southwark), free, just turn up, 25 April-6 May
THE THEMERSONS: This talk examines the lives of Franciszka and Stefan Themerson, a couple from Warsaw who fled to Britain to escape Hitler's regime, and the contribution they made to literary and artistic life in Britain. The Wiener Library, free, just turn up, 6.30pm-8pm
TEMPLAR POETRY: Poet Olive Broderick launches her debut collection, Night Divers, alongside Kathleen Jones launching her poetry pamphlet, Mapping Emily. Keats House (Hampstead), free, book ahead, 7pm-8.30pm
OH BOY! COMEDY: Bec Hill headlines this comedy night, alongside Kat Bond, Harry Deansway and Robin Hill. The Rose and Crown (Kentish Town), free/pay what you want, just turn up, 7.30pm
Wednesday 26 April
KENNEL CLUB TOUR: A rare chance to get inside the Kennel Club's new headquarters in Piccadilly. Learn about what the canine-centric organisation does, and visit its art gallery and library. Kennel Club (Piccadilly), £5, book ahead, 11am
DISEASE ERADICATION: We can't guarantee this lecture will be glamorous, but it sounds fascinating. Learn all about attempts to eradicate diseases such as polio, and why such attempts haven't been successful so far. Museum of London, free, just turn up, 6pm-7pm
100 DAYS OF TRUMP: It's been 100 days since President Trump came to power, and to mark the occasion, a panel of experts are hosting a debate about the administration so far, and implications for the future. LSE, free, just turn up, 6.30pm-8pm
SCIENCE MUSEUM LATES: It's the last Wednesday of the month so Science Museum is open late for its monthly adults-only event. The theme this month is food and drink — learn all about food science through talks, hands-on events, and of course, the legendary silent disco. Age 18+. Science Museum (South Kensington), free (charge for some events), just turn up, 6.45pm-10pm
MUDLARKING: Greenwich Historical Society hosts mudlarking expert Nicola White who will be sharing her experiences of finding items on the Thames foreshore to use her art. James Wolfe School (Greenwich), £3, 7.15pm
Thursday 27 April
WHEN SPECIES MEET: Specimens from the Grant Museum are being used to tell the stories of what happens when two distinct species meet. Hear from scientists and conservationists about how species have been lost, and conservation hopes for the future. Grant Museum of Zoology, free, book ahead, 7pm-8.30pm
SYRIAN CONFLICT: This new Imperial War Museum exhibition highlights the origins and human impact of the current Syrian conflict through photos and personal objects and stories. Imperial War Museum (Lambeth), free entry, just turn up, 27 April-3 September
SLEEP WELL: Set yourself on track for a good night's sleep — learn how to make your own wheat pillows, lavender bags and camomile tea bags at this workshop. Lower Marsh (Waterloo), free, just turn up, noon-3pm
OVER THE RAINBOW: Nicola Field, an original member of Lesbians and Gays Support the Miners is discussing a new, expanded edition of her 1995 book Over The Rainbow: Money, Class And Homophobia. Review bookshop (Peckham), £5, book ahead, 7pm-9pm
EXHIBITION LAUNCH: Beautiful Glorious Chaos is the name of this bar's latest exhibition, and that's what we're expecting at the launch night tonight. The Book Club (Shoreditch), free, just turn up, 7pm-12am
BLACK CABARET QUEEN: Celebrate the life and work of London-born singer Evelyn Dove. Speaker Stephen Bourne has just written a book about the cabaret performer. Black Cultural Archives (Brixton), £3, book ahead, 1pm-2pm
Friday 28 April
LONDON ARTWORKS: We love these renderings of London by artist Paul Catherall — they've even been used by TfL. Now a collection of his works in the capital are going on display in an exhibition. For Arts Sake (Ealing), free, just turn up, 28 April-21 May
FREE FILM FESTIVAL: Herne Hill Free Film Festival kicks off today with a screening of The BFG — and an appearance by the star of the film (and local resident) Mark Rylance. Other films lined up for the festival include Victoria, Easy Rider, and The Big Lebowski. Various locations, free, book ahead, 28 April-29 May
WAR ARTISTS: Museum curator Emma Mawdsley leads a tour around the War Paint exhibition, discussing how, in an age before photography, artist impressions were the only images of war available. National Army Museum (Chelsea), free, book ahead, 11.30am
FRIDAY TONIC: Kick start your weekend with some live music courtesy of some of the London Philharmonic Orchestra's youngest stars, who will perform 20th- and 21st-century music that has been written in the face of adversity and under political regimes. Southbank Centre, free, just turn up, 5.30pm
NATURAL HISTORY LATES: The theme of this month's late is sounds in nature. Find out how animals sounds are used to identify and classify them and get hands-on at pop-up science stations, or just explore the museum's exhibits after hours. Natural History Museum (South Kensington), free entry (charge for some activities), just turn up, 6pm-10pm
FILM CLUB: Head to Chapel Film Club for a screening of 2011 film Midnight In Paris, about a writer who gets swept back in time on a visit to the French capital. The Old Chapel (Chislehurst), £5, book ahead, 8pm (doors at 7.30pm)
Saturday 29 April
BANK HOLIDAY: Lacking inspiration? Take a look at our guide to how to spend a bank holiday weekend in London.
THE LONDONERS: From today, Guildhall's exhibition Portraits Of A Working City expands into Guildhall Yard, with 50 portraits not used in the original exhibition. The images portray Londoners from the 15th century to the present day going about their work in everyday jobs. Guildhall Yard, free entry, just turn up, 29 April-23 May
WILD WEEKEND FESTIVAL: London's newest nature reserve hosts a family-friendly wildlife festival with tours, workshops, talks and debates, a farmers's market and more. Woodberry Wetlands (Stoke Newington), free entry, just turn up, 9am-6pm, 29-30 April
GLUTEN-FREE FESTIVAL: Limehouse Social Market celebrates its first birthday with a gluten-free festival. Expect gluten-free street food (crepes, pizza, hummus, cupcakes), a farmers' market, live music, graffiti workshops and more. Limehouse Basin, free entry, just turn up, 11am-5pm
VAISAKHI: All Londoners are invited to Trafalgar Square to celebrate Sikh festival Vaisakhi. Events include live performances, food and drink, children's activities and turban-tying demonstrations. Trafalgar Square, free, just turn up, noon-6pm
ELIZABETHAN ISLINGTON: Acquaint yourself with the Islington of 1583 on this Elizabethan Islington walk, which ties in with this year's Cityread events. Hear stories of archery contests, Huguenot migrants and more. Finsbury Library, free, book ahead, 11am-noon
Sunday 30 April
BENGALI MUSIC: The Bengali Baul and Vaishnav Music Festival culminates at Rich Mix today with performances of Bengali folk music, poetry translated into English, and Sufi dance. Rich Mix (Shoreditch), free entry, just turn up, 6pm