All week
BEAUTIFUL BUTTERFLIES: Still time to see the photogenic and free butterfly biosphere which has popped up in Mayfair. Designed by Bompas & Parr, it gives people a chance to get up close to the winged beauties, while teaching them about the challenges wild butterflies are facing. Grosvenor Square (Mayfair), free, just turn up, until 15 September
SMOKE AND MIRRORS: Last chance to see the current exhibition Smoke and Mirrors: The Psychology of Magic. Some of the secrets of the trade are revealed, including the fact that most tricks work thanks to the perception of the audience, rather than the magician performing them. Examples of early tricks, photos, and a silent film also feature. Wellcome Collection (Euston), free, just turn up, until 15 September
FREE FILMS: Almost 20 film screenings take place in south-east London for the Charlton and Woolwich Free Film Festival, and as the name suggests, you won't have to pay a penny to see any of them. Watch Matilda in a library (apt), see Life of Brian in a pub, and catch climbing documentary Free Solo at a climbing centre. Various locations, free, just turn up, 6-14 September
TOTALLY THAMES: An insight into London's dirty history is one of the highlights of the free events on the Totally Thames programme this week. They run alongside ongoing events including the Ship of Tolerance, and a smelly exhibition. Various locations, 1-30 September
Monday 9 September
TINY TROOPERS: Younger kids are catered for at National Army Museum's toddlers' session, Tiny Troopers. The sensory session for under 5s involves singing, games and crafty activities, and this month's theme is music. National Army Museum (Chelsea), £5, book ahead, 10am/11.20am
Tuesday 10 September
HOUSE OF VOGA: Strike a pose on a floating pocket park at House of Voga's free, open air class. Voga is a blend of yoga and voguing, aimed at those who like the idea of yoga but want a cardio workout. Merchant Square (Paddington), free, book ahead, 6pm-7pm
ROCKY HORROR: Get ready to do the Time Warp, at a free, open-air screening of the Rocky Horror Picture Show. Bring your own picnic mat to watch the 1975 film about a couple lost in a storm who discover the mansion of Dr. Frank-N-Furter. Canada Square Park (Canary Wharf), free, just turn up, 9pm
Wednesday 11 September
FINANCE AND MENTAL HEALTH: Jill Kennedy McNeil's exhibition Despite Numerous Attempts To Contact You tackles the links between personal finance and mental health. The gallery's curated to represent a domestic setting, textile designs feature letters from debt collection agencies, and excerpts from personal communications with family and friends are also on display. One Paved Court (Richmond), free, just turn up, 11-22 September
CINECLUB BRAZIL: Head to the Brazilian Embassy for a screening of 45 Days Away From You, a film by Brazilian director Rafael Gomes. It's the story of a man who visits three friends in three different locations following a relationship break-up. Brazilian Embassy (Trafalgar Square), free, book ahead, 6.15pm-8.30pm
THINK PINK: For one night only, attend the Think Pink exhibition. It showcases illustrations by 20 artists, interpreting key moments in fashion through shades of pink. Why pink? To represent Breast Cancer Care, as all of the works are for sale in aid of the charity. SHOWStudio (Victoria), free entry, book ahead, 6.30pm-8.30pm
Thursday 12 September
SCIENCE CITY: Science Museum opens a new, permanent gallery, and it's all about London. Science City focuses on the capital's contributions to science between 1550 and 1800. Highlights include a copy of Newton's Principia Mathematica (which some would argue is the most important book ever published), Newton's telescope, and Robert Hooke's microscope and illustrations. Science Museum, free entry, just turn up, from 12 September
PIGS OF PARADISE: Heard of the pigs which swim in the seas surrounding a tropical island in the Bahamas? Author T.R. Todd has written a book, Pigs of Paradise, about how they came to be there, and why many of them died in 2017. Todd discusses his book, followed by a screening of a new feature-length film based on the book. Stanfords (Covent Garden), £4, book ahead, 7pm-8.45pm
Friday 13 September
AFRICA UTOPIA: For three days, Southbank Centre celebrates the African continent and its diaspora, and the effect they've had on art, culture, gender and race here in the UK. Free events taking place over the Africa Utopia weekend include a voguing workshop, a children's cartoon show and an African marketplace. Southbank Centre, various prices, 13-15 September
CLASSIC 80S: Dance the night away to classic 80s hits, including new wave, synth-pop and new romantic sounds. Outfits from the decade very much encouraged — think big shoulder pads and bouffed hair. Star of Kings (King's Cross), £4, book ahead, 7pm-1am
DOG-FRIENDLY CINEMA: Pooches and popcorn mix at this dog-friendly cinema event. Take your canine friend along to a screening of Dean Spanley, a 2008 film which includes a scene of dogs running through a field. If the weather's good, it's an outdoor screening, otherwise things head inside — dogs welcome either way. Part of Charlton and Woolwich Free Film Festival. Charlton House, free, just turn up, 8.30pm-10.30pm
Saturday 14 September
LONDON DESIGN FESTIVAL: A colourful pop-up lounge by artist Camille Walala is one the highlights of the London Design Festival programme, which begins today. Some of the events are charged, but there are plenty of free exhibitions and installations dotted around town for the duration of the festival. Various locations and prices, 14-22 September
GREAT RIVER RACE: An epic 330 boat crews go head to head in the Great River Race, which covers a 21.6 mile route from Docklands to Ham. Bag yourself a spot on the riverbank to see gigs, skiffs, cutters, naval whalers, Chinese dragon boats, Hawaiian war canoes, shallops, skerries, wherries and other types of vessel go racing past. Millwall-Ham, free, just turn up, 11.20am
HIDDEN RIVER FESTIVAL: The New River was built by hand over 400 years ago, and still supplies Londoners with fresh drinking water today. Celebrate it at the Hidden River Festival, which includes canoeing, a treasure hunt, art and craft activities, and entertainment from street dance to circus skills. Woodberry Wetlands (Harringay Green Lanes), free, just turn up, 12pm-6pm
Sunday 15 September
DINOSAUR DAY: Get up close to the Crystal Palace dinosaurs at the annual Dinosaur Day. Get access to the usually-private island in the middle of the lake where the dinosaurs reside, via tours with experts. Other family-friendly activities include storytelling and crafts. Crystal Palace, free, book ahead, 10am-4.30pm
ALLOTMENT OPEN DAY: Have a nosey inside the allotments of Kensington Gardens on this open day. Meet the shire horses of the Royal Parks, learn what's grown — and how — in the allotments, and keep children busy with see sowing and bug hunts. Kensington Gardens, free, just turn up, 11am-4pm
SUMMER STREETS: The final Summer Streets event of 2019 takes place on Regent Street, closing the busy thoroughfare to vehicle traffic for an afternoon of activities. The festival-style event includes talks, catwalk shows, street food from local restaurants, and activities, offers and competitions inside the shops. Full programme here. Regent Street, free, just turn up, 12pm-5pm
