Songfacts®:

• "Today is Gonna Be a Great Day" is the full-length version of theme song to the Disney TV show Phineas and Ferb, which is about about two step brothers who do stuff like build rollercoasters and time machines on their summer vacation. The song (and the theme) are performed by Bowling For Soup, whose hits include "1985" and "Girl All The Bad Guys Want." The additional lyrics for the extended version were written by the group's lead singer Jaret Reddick, who told Songfacts how he ended up working on the show. Said Reddick: "I got a really random call from some folks at Disney and they were developing this show, and the two creators were Dan Povenmire and Swampy Marsh, who had both worked on The Simpsons together; Dan went on to work on Family Guy amongst other things, and Swampy went on to create a show called Rocko's Modern Life. They came together at a restaurant over dinner and Dan drew some pictures on a napkin and said, 'I'm thinking about doing this cartoon, but I won't do it without you.' So the idea was born.
  
  And luckily enough for me, they were both big Bowling for Soup fans. And so as they were developing this they had the first 13 episodes drawn and voiced and stuff, but incomplete. They had this theme song that was about 25 seconds, 30 seconds long, and they wanted to turn it into an actual radio single. And so they contacted me directly and said, 'Would you be interested in performing a theme song, but also writing a song around it to try to make it into a 3 and a half minute song that we can play on the radio?'
  
  So I was like, 'Sure, yeah, I'd love to do that.' And I was headed out to L.A. anyway, I was actually working on an album that we were doing. I went in and I had this meeting with the head of music and animation there at Disney, and it was just a really cool experience. They gave me a tour of the Disney lot. And as many songs as I've done for Disney movies in the past, I've never actually been on the campus.
  
  So we went to lunch, and then after lunch they were like, 'Hey, do you want to see some of the episodes?' So I walk into this conference room and there's my name and the Phineas and Ferb guys up on this big screen, and they showed me the first 13 episodes, unfinished. I took notes and I flew home the next day and I wrote 'Today is Gonna Be A Great Day' around the original theme song, and it took me about 20 minutes. I sent them an acoustic demo, and they were just like, 'We love this!' We went in the studio, I think just a few days after that, and recorded the song with my guys in Bowling for Soup. And the rest, as they say, is history."
• On Phineas and Ferb, Jaret Reddick also plays Danny, the lead singer of the '80s group Love Händel, which the cartoon brothers reunited for the sake of their parents, who first kissed at a Love Händel concert. Bowling for Soup are also involved in some of the many musical numbers that have become a specialty on the show. Reddick explained that Povenmire and Marsh write these numbers: "Martin Olson is the head writer and usually it's those three sitting in a room. So when I'm lucky enough to be in L.A. and be invited into that room, it's always great, because they're super open to my ideas. And I write from a completely different world. Dan was in a band forever and Swampy's really musical and Martin's musical, they're all musical guys. But I'm a little bit younger and I write all different kinds of music. So it's a fun experience, because they'll just be like, 'We would have never thought of that.' And Dan tells people, 'Jaret taught me how to make this chord' and whatever. So that makes you feel really, really good, whereas these guys are just uber successful now. And they don't forget where it all comes from. They're great people. It's an amazing, amazing organization."