Imagine if kids ruled the world. What a place that would be! In the fourth episode of the children's reality series Election, CBBC continues its search to find a true leader among the kids of the UK.

The series is presented by Angellica Bell, and in this fourth programme the remaining eight candidates have to learn to get their facts right and practise their public speaking. Taking over a busy tour boat on the Thames, the kids have to give guided tours of London to tourists. But a professional tour guide has been planted in the audience to ask some difficult questions - will this phase the candidates?

As ever, their every move will be watched and assessed by Jonathan Dimbleby, the series' judge. This political journalist has interviewed Brown, grilled Thatcher, and taken Blair to task, but what will he make of these pint-sized politicians in this test of their ability to win over an audience? And yet again, one of our budding leaders will have to go home when Jonathan utters his catchphrase line: 'Your campaign's over'. Show less