1. Paddington Gardens (Moxton Street)
Hidden behind the high street and attached to a small park this playground has lots to keep Dingus occupied.
There are parts for younger babies/toddlers and older children too.
Climbing frames, slides, zip wires etc.
Paddington Gardens Marylebone, London W1U 4AN https://maps.app.goo.gl/GKfTNbpRxTfBxVUc7
2. Marylebone Green Playground in Regents Park
There are four playgrounds in the Park (if you include Primrose Hill) but this was the best but the one i found last.
Lots of sand, massive slides and rock climbing will keep the older children happy but also a special toddler area.
Marylebone Green Playground The Regent's Park, Chester Rd, London NW1 4LL https://maps.app.goo.gl/6AuJcGkdf2SBukFw8