0:00:06 > 0:00:09Afternoon all, it's Ayshah here live with Tuesday's Newsround with loads
0:00:09 > 0:00:10of great stuff to tell you...
0:00:10 > 0:00:12We get a pigeon's-eye view of pollution....
0:00:12 > 0:00:14And...
0:00:14 > 0:00:23A flying visit from author David Walliams to answer your questions...
0:00:26 > 0:00:29Gary Barlow has spoken out against reports that Five-to-Five -
0:00:29 > 0:00:32the boy band who won TV show Let It Shine -
0:00:32 > 0:00:32would just be the backing band in a musical about Take That.
0:00:35 > 0:00:37Reports have said that the boys wouldn't be the main
0:00:37 > 0:00:40stars of the show, but
0:00:40 > 0:00:43the people behind the musical told Newsround, that the rumours
0:00:43 > 0:00:46were "simply not true".
0:00:46 > 0:00:49A special project helping to measure pollution has had help from some
0:00:49 > 0:00:50feathered scientists.
0:00:50 > 0:00:56Yes, pigeons are being used to find out more about air quality.
0:00:56 > 0:00:58Martin has been coo-vering the story...
0:00:58 > 0:01:01Pigeons!
0:01:01 > 0:01:04We see them all the time in the city, trying to find bits
0:01:04 > 0:01:05of food and scurrying about.
0:01:05 > 0:01:12But how are they linked to pollution?
0:01:12 > 0:01:14Apart from both beginning with the letter P?
0:01:14 > 0:01:16Well, scientists are using pigeons to gather information
0:01:16 > 0:01:18by strapping these small sensors to the backs of them.
0:01:18 > 0:01:19Why?
0:01:19 > 0:01:22It is known that pollution that comes out of cars with diesel
0:01:22 > 0:01:24engines rises to rooftop levels.
0:01:24 > 0:01:27But, what is not known, is what happens next to the pollution?
0:01:27 > 0:01:31Where does it go?
0:01:31 > 0:01:33Step in Pigeon Patrol!
0:01:33 > 0:01:35I kind of thought, well...
0:01:35 > 0:01:43Birds fly everywhere.
0:01:43 > 0:01:46If they can carry our sensors, and if they can be accurate
0:01:46 > 0:01:48enough and tiny enough, we can understand the dispersion
0:01:48 > 0:01:49of air pollution around the city.
0:01:49 > 0:01:51Birmingham University are carrying out a test flight.
0:01:51 > 0:01:52I feel nervous.
0:01:52 > 0:01:54This is the first time that we've done this.
0:01:54 > 0:01:57One of the pigeons is fitted with a small lightweight sensor
0:01:57 > 0:02:05and camera to record the flight.
0:02:05 > 0:02:06I'm happy with that.
0:02:06 > 0:02:08I just hope they go home!
0:02:08 > 0:02:10Just six minutes later, the pigeons are back and the sensor
0:02:10 > 0:02:12is still on its back.
0:02:12 > 0:02:13The light is still flashing.
0:02:13 > 0:02:20That's a good sign!
0:02:20 > 0:02:28Rick and his team have been able to find out
0:02:28 > 0:02:31the route the pigeons took, and the temperature of the air.
0:02:31 > 0:02:33The information will help them figure out how pollution
0:02:33 > 0:02:34moves around big cities.
0:02:34 > 0:02:35What's this pigeon called?
0:02:35 > 0:02:36I haven't got a name for him.
0:02:36 > 0:02:38I call him number 80!
0:02:38 > 0:02:40So thanks, pigeon number 80.
0:02:40 > 0:02:50You've done everyone proud!
0:02:50 > 0:02:50Thanks
0:02:50 > 0:02:52Thanks Martin!
0:02:52 > 0:02:54Whether it's Gangsta Grannies, awful aunties or demon dentists,
0:02:54 > 0:02:57author David Walliams is not afraid to tackle difficult subjects,
0:02:57 > 0:02:58whilst also making us giggle.
0:02:58 > 0:03:00His latest story - Grandpa's Great Escape -
0:03:00 > 0:03:02is about the adventures of a boy and his forgetful grandfather.
0:03:02 > 0:03:05David came into the BBC earlier today, to answer some
0:03:05 > 0:03:08of your burning questions...
0:03:08 > 0:03:13Now, in something of a panic, the boy pulled the nearest handle.
0:03:13 > 0:03:16And the ancient tank surged forward at a terrific speed.
0:03:16 > 0:03:17Smash!
0:03:17 > 0:03:22It demolished the wall of the museum with laughable ease!
0:03:22 > 0:03:25What is your favourite book from when you were younger?
0:03:25 > 0:03:31Charlie and the Chocolate Factory.
0:03:31 > 0:03:34I used to go to a local library with my mum and dad
0:03:34 > 0:03:35and sister every two
0:03:35 > 0:03:38weeks, and that is the book that got me reading.
0:03:38 > 0:03:40You mention that book and everybody knows it,
0:03:40 > 0:03:43everybody has read it.
0:03:43 > 0:03:45That's one of the greatest children's books of all time.
0:03:45 > 0:03:47What made the teacher hate children so much?
0:03:47 > 0:03:49The reason is that evil teachers are much more
0:03:49 > 0:03:50interesting than nice teachers.
0:03:50 > 0:03:52If you are writing a teacher character,
0:03:52 > 0:03:54think about Miss Trunchbull who throws children
0:03:54 > 0:03:56around by their pigtails and they fly out the window.
0:03:56 > 0:03:59But yes, I thought it was much more fun to have a headteacher
0:03:59 > 0:04:00who hates children.
0:04:00 > 0:04:02What inspired you to become a really good writer?
0:04:02 > 0:04:05I suppose I got into writing because I was doing comedy,
0:04:05 > 0:04:08and I knew that comedians, when I was a kid I knew
0:04:08 > 0:04:10that comedians generally wrote their own material,
0:04:10 > 0:04:14and that got me into writing.
0:04:14 > 0:04:16Then, I realised that writing really was for me the most
0:04:16 > 0:04:18creative part of it all.
0:04:18 > 0:04:22And I love that idea of a blank page and you create characters
0:04:22 > 0:04:27and situations and scenes.
0:04:27 > 0:04:30They leapt up onto the wing and climbed into the cockpit.
0:04:30 > 0:04:33As with most World War II fighter planes, there was just one seat.
0:04:33 > 0:04:36So, the boys sat on his grandfather's lap.
0:04:36 > 0:04:37Cosy in here, isn't it, Squadron leader?
0:04:37 > 0:04:38Remarked the old man.
0:04:38 > 0:04:42For the first time in his life, Jack was sitting in a real Spitfire.
0:04:42 > 0:04:43His dream was coming true.
0:04:46 > 0:04:46Great
0:04:46 > 0:04:48Great questions!
0:04:48 > 0:04:49That's it from us.
0:04:49 > 0:04:50Newsround's back at 07:40am tomorrow.
0:04:50 > 0:04:53Don't forget to go online to find out why pandas are black and white -
0:04:53 > 0:04:55I always wondered that!
0:04:55 > 0:04:55See ya!