A funny thing is happening in British cities this summer. Despite, or perhaps because of, the new age of austerity, perfectly sane adults are acting like children.

Childlike excitement is evident in Trafalgar Square where an enormous maze has sprung up (if you’re London-based, today is your last chance to get lost in it). Also in London, 100 ping pong tables have appeared in various locations, from Soho Square to Westfield shopping centre. A little sign on the bats asks ‘please put me back’. The whole thing feels very ‘Alice in Wonderland’.

Meanwhile in Manchester, today sees the launch of a huge three-day picnic event. Piccadilly Gardens has been transformed with benches, bunting and stalls selling picnic food, and other public spaces will be hosting themed picnics too.

Scotland is about to be plunged into a world of play too, with the Edinburgh Festival kicking off later this month, when street theatre will be everywhere you turn on The Royal Mile.

It would have pleased American Professor Randy Pausch. In 2007, he was diagnosed with pancreatic cancer and given months to live. Instead of wallowing in self-pity, he gave an upbeat lecture at Pittsburgh’s Carnegie Mellon University entitled: ‘The Last Lecture: Really Achieving Your Childhood Dreams.’ It became a YouTube sensation and encouraged millions of people to remember how they felt as children. ‘I don’t know how to not have fun,’ Pausch said. ‘I’m dying, and I’m having fun, and I’m going to keep having fun every day I’ve got left. Never lose the childlike wonder.’

So take his advice, and throw yourself into some childish fun this weekend.