Normally it is very hard to get a politician to take responsibility. Today, David Cameron and Ed Miliband battled to be more mature than the other.

But it was PMQs – and both leaders are better schooled in playground politics than the teachers' common room.

It was rowdy (Speaker Bercow had to interrupt the exchange five times).

It was Punch and Judy on the picket line.  

Miliband began by citing Sue Foster-Agg, of the Vaynor First School in Redditch, who is striking for the first time in her life.

She was the headteacher praised by David Cameron in June for not closing her school during the last round of strikes.

Now she says: "I have not seen any progress so I have decided to follow my union's advice to strike."

Strong stuff – but the prime minister seemed nonplussed:  "The reason that people are going on strike is because they object to the reforms we are making on public sector pensions."

Miliband shook his head in that way that very grown-up people do.

He told the House he's heard the PM is "privately delighted that unions have walked into his trap".

"He's not being straight with people."

Cameron's voice rose a few pitches in a very un-adult way. "It is extraordinary that what he has told the House is completely and utterly untrue," he said.

The PM pointed out that Miliband appears to have changed his mind on the strikes.

"Today he now backs the strikes," said Cameron. "Why? Because he is irresponsible, left wing and weak."

Miliband returned the taunt with a bit of hearsay. "He is the one – and he didn't deny it – who's saying they are privately delighted because they've walked into his trap," he said.

"I do not welcome these strikes one bit," denied Cameron. "I think we have made a very reasonable, very fair offer. This government has to make responsible decisions."

"The party opposite are in the pocket of the trade union leaders," said Cameron, returning to one of his favourite jibes.

The noise level forced Bercow to make a further interjection (and to tell the PM that a one sentence answer will suffice).

"I'll wait to his next trade union-sponsored answer then give an answer," responded Cameron.

Miliband couldn't resist that dig. "Better that than millions from Lord Ashcroft," he said.

By now, Punch was hitting Judy over the head with a placard.

"They are all shouting in unison," said Cameron, gesturing to the Labour benches. "Or should that have been, they are all shouting on behalf of Unison."

(Oh, dear. We've descended into word play.)

Cameron finished: "We are being tested by these difficult economic times. We will meet that test. He [Miliband] is being tested too. He will show that he is weak, left wing and irresponsible."

He liked that last line so much, he used it twice.

If today's PMQs is the best they can do in this test of our economic times, Cameron and Miliband might need to take a resit.

Tags: David Cameron's speech, Ed Miliband, PMQs