Here are the list of Dora the explorer episodes That were created by Valerie Walsh  Valdes, Chris Gifford and Eric Weiner:

Season 1 
 The Big Red Chicken (Episode created: August 14, 2000)
 Lost and Found (Episode created: August 15, 2000)
 Choo Choo (Episode created: September 11, 2000)
 Hic-Boom-Ohhh (Episode created: August 21, 2000)
 We Scream for Ice Cream (Episode created: September 4, 2000)
 Three Little Piggies (Episode created: September 25, 2000)
 Treasure Island (Episode created: September 18, 2000) 
 Beaches (As a Pilot for show series: June 12, 1999 -  As a Episode for show series: August 28, 2000)
 Big River (Episode created: October 9, 2000)
 Berry Hunt (Episode created: October 30, 2000)
 Wizzle Wishes (Episode created: November 13, 2000)
 Grandma's House (Episode created: November 13, 2000)
 Surprise (Episode created: November 20, 2000)
 Sticky Tape (Episode created: November 27, 2000)
 Bouncing Ball (Episode created: December 4, 2000)
 Backpack (Episode created: December 11, 2000)
 Fish Out of Water (Episode created: December 25, 2000)
 Bugga Bugga (Episode created: December 18, 2000)
 Little Star (Episode created: January 22, 2001)
 Dora Saves the Prince (Episode created: February 5, 2001)
 El Coquí (Episode created: May 2, 2001)
 The Chocolate Tree (Episode created: May 3, 2001)
 Te Amo (Episode created: October 1, 2001)
 Pablo's Flute (Episode created: October 8, 2001)
 To the Treehouse (Episode created: May 4, 2001)
 Call Me Mr. Riddles (Episode created: October 15, 2001)

Season 2 
 The Big Storm (Episode created: March 11, 2002)
 ¡Rápido, Tico! (Episode created: November 18, 2002)
 The Magic Stick (Episode created: March 12, 2002)
 The Missing Piece (Episode created: March 18, 2002)
 Lost Squeaky (Episode created: March 25, 2002)
 Rojo, the Fire Truck (Episode created: March 19, 2002)
 Lost Map (Episode created: September 16, 2002)
 El Dia de Las Madres (Episode created: May 8, 2002)
 The Golden Explorers (Episode created: April 1, 2002)
 A Present for Santa (Episode created: December 11, 2002)
 Doctor Dora (Episode created: March 26, 2002)
 Pinto, the Pony Express (Episode created: September 18, 2002)
 León, The Circus Lion (Episode created: July 14, 2003)
 The Big Piñata (Episode created: September 19, 2002)
 The Happy Old Troll (Episode created: September 20, 2002)
 Super Map (Episode created: October 14, 2002)
 A Letter for Swiper (Episode created: January 20, 2003)
 To the Monkey Bars (Episode created: April 28, 2003)
 Dora, La Musico (Episode created: January 27, 2003)
 Hide and Go Seek (Episode created: May 5, 2003)
 Click! (Episode created: November 5, 2002)
 Egg Hunt (Episode created: April 20, 2003)
 Super Spies (Episode created: April 24, 2003)
 School Pet (Episode created: May 12, 2003)
 Whose Birthday is It? (Episode created: May 26, 2003)
 Quack! Quack! (Episode created: May 19, 2003)

Season 3 
 Dora Had a Little Lamb (Episode created: August 26, 2003)
 Stuck Truck (Episode created: October 8, 2003)
 Louder! (Episode created: April 21, 2004)
 Roberto the Robot (Episode created: October 9, 2003)
 The Big Potato (Episode created: October 10, 2003)
 Journey to the Purple Planet (Episode created: October 28, 2003)
 The Lost City (Episode created: June 3, 2003)
 Meet Diego (Episode created: October 7, 2003)
 Save the Puppies (Episode created: October 14, 2003)
 Por Favor! (Episode created: October 15, 2003)
 Baby Dino (Episode created: October 22, 2003)
 Boots' Special Day (Episode created: October 24, 2003)
 To The South Pole (Episode created: October 27, 2003)
 Dora Saves the Game (Episode created: November 11, 2003)
 Boo! (Episode created: October 29, 2003)
 What Happens Next? (Episode created: October 16, 2003)
 Rescue, Rescue, Rescue! (Episode created: October 13, 2003)
 Boots' Cuddly Dinosaur (Episode created: April 19, 2004)
 The Super Silly Fiesta (Episode created: April 12, 2004)
 The Fix-It Machine (Episode created: October 17, 2003)
 Baseball Boots (Episode created: October 23, 2003)
 Best Friends (Episode created: October 6, 2005)
 ABC Animals (Episode created: April 22, 2004)
 Job Day (Episode created: April 20, 2004)
 Dora's Pirate Adventure (Episode created: January 27, 2004)

Those are the list of Dora the explorer episodes that ran from, August 14, 2000 until August 9, 2019. The first episode was The Big Red Chicken (August 14, 2000) and the last episode was Let's Go to Music School (August 9, 2019)

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