Over the course of the series, fans could enter many different contests, giveaways, challenges, and sweepstakes where they could win cool prizes such as BSC merchandise, trips to Disney World or New York City, a visit from Ann M. Martin, a scholarship, or a book dedicated to them.
|Form Your Own Baby-sitters Club||June 30, 1987 / while supplies last||Membership charter, story in BSC Newsletter|
|Trivia Quiz||December 31, 1987||Kid Kit|
|Super Special Contest- Vote for your favorite baby-sitter||December 31, 1988||3-day trip to Disney World|
|Baby-sitters Night Shirt Giveaway||May 31, 1989||Baby-sitters Night Shirt|
|Super Trivia Contest||November 30, 1989||Dinner with Ann M. Martin and 3 friends|
|Little Sister Camera Giveaway||November 30, 1989||Vivitar Compact 35MM camera|
|Fabulous Summer Giveaway||August 31, 1990||Little Sister Belt Pack|
|Baby-sitters Club Adventure Giveaway||November 30, 1990||3-day trip to New York City|
|Create a New Baby-sitter Contest*||1990||$100 for school, profile in Fan Club newsletter|
|Fun in the Sun Giveaway||March 31, 1991||Beach Towel|
|Make-a-Wish Giveaway||March 31, 1991||Wish granted up to $100|
|Baby-sitters Club Video Giveaway||May 31, 1991||BSC Video|
|Baby-sitters Club Mystery Giveaway*||Sept 30, 1991||signed hardcover of book #1|
|Vote for Your Favorite Baby-sitter||October 31, 1991||Baby-sitters Club party with Ann M. Martin|
|Little Sister Disney World Giveaway||November 30, 1991||3-day trip to Disney World|
|Baby-sitters Club Snowbound Giveaway||March 31, 1992||Snowbound Kit (Backpack, Sleeping bag, nightshirt, Videos, Board Game)|
|Karen's Scavenger Hunt||March 31, 1992||roller skates, baseball hat, flashlight, backpack, teddy bear|
|BSC Neat Boy Giveaway*||August 31, 1992||BSC Nightshirt|
|Super Special Trivia Giveaway||November 30, 1992||Locket Charm Bracelet|
|Little Sister Perfect Day Giveaway||November 30, 1992||$250 and three personalized "Three Musketeers" t-shirts|
|Winter Super Special Giveaway||December 1, 1992||5-day trip to Disney World|
|Mini-Mystery Giveaway*||December 31, 1992||BSC Fun Pack|
|Baby-sitters Club Look-Alikes*||Spring 1993||Your picture in a BSC Fan Club newsletter|
|Little Sister Summer Friendship Giveaway||October 31, 1993||Little Sister Stationery Kit|
|Summer Super Special Giveaway||November 30, 1993||3-day trip to Universal Studios in Orlando, FL|
|Baby-sitters Club Winter Challenge||March 31, 1994||$10,000 Scholarship savings bond|
|The BSC Remembers Sweepstakes||October 31, 1994||$2500 cash prize towards any artistic, academic or sports pursuit|
|Name the Twins Contest||January 31, 1995||Winning names featured in series, book dedicated to contest winner|
|BSC Summer Sweeps||October 31, 1996||Featured in future BSC story, LA Gear wardrobe, videos, book|
|California Diaries Getaway Sweepstakes||October 10, 1997||3-day trip to California|
|Friends Forever New York City Getaway Sweepstakes||August 15, 1999||3-day trip to NYC including one visit with Ann M. Martin|
* Contest exclusive to BSC Fan Club members
BOLD - Baby-sitters Little Sister contest
- Form Your Own Baby-sitters Club (book #1,2,3,7,8) - Write your funniest baby-sitting tip or funniest baby-sitting experience, and get a Membership Charter, Emergency Info sheets, and the chance for your story to appear in The Baby-sitters Club Newsletter. In books #1, 2, and 3 this contest had a deadline of June 30, 1987. In books #7 and 8, the deadline was "while supplies last". Since book #8 was first published in November 1987, the effective deadline was probably end of 1987/very early 1988 since the ad did not appear in book #9. A 1989 New York Times articles mentions that this kit included a pad of Important Phone Numbers to be filled out by parents, an oath that members must sign in which they promise to be become the best baby-sitters they can, brochures to advertise the club, and a newsletter with sitting tips.
- Trivia Quiz/ Win a Kid Kit (book #6) - Answer 10 Trivia questions about books #1-6 correctly and you could win one of five Kid Kits (just like the ones the BSC use), packed with activities and books to keep your baby-sitting charges busy for hours. 100 runners-up will win the official Baby-sitters Club Kit and Newsletter.
- Super Special Contest (book #19, SS#1) - Vote for your favorite baby-sitter, and you could be the random winner of a drawing for a 3-day trip to Magic Kingdom and Epcot Center at Disney World. In book #25, the winner of the drawing, the favorite baby-sitter, Stacey McGill, and the results of the poll were revealed.
- Super Trivia Contest (book #29) - Answer four questions true or false, and you could win a visit from Ann M. Martin for you and three of your friends. 2nd prize is BSC T-shirts and 3rd prize is BSC socks. In book #36, the winner, Sara, was revealed.
- Baby-sitters Night Shirt Giveaway (book #21-23) - win a baby-sitters club night shirt (light blue with BSC logo on the front)
- Little Sister Camera Giveaway (LS #5-6) - Fill in the coupon, and you could be one of 25 winners of a Vivitar Compact 35MM camera
- Little Sister Fabulous Summer Giveaway (LS # 8,9,10) - Send in a photo of your favorite or funniest haircut, and you could be one of 150 winners of a Baby-sitters Little Sister Belt Pack.
- BSC Adventure Giveaway (book #36-39) - Guess the location of the next Super Special adventure, and you could win a 3-day trip to New York City. 2nd prize winners get BSC Sun Visors.
- Create a New Baby-sitter Contest (BSC Fan Club newsletter) - create a profile of a new baby-sitter, and win $100 for back-to-school shopping, and get the profile published in a fan club newsletter.
- Fun in the Sun Giveaway (book #40, SS #5) - Fill in the coupon, and you could be one of 200 winners of a BSC Beach Towel.
- BSC Video Giveaway (book #43-44) - Fill in the coupon, and you could be one of 25 winners of a live-action Baby-sitters Club video.
- Vote for your favorite baby-sitter (book #45-46) - Grand prize wins a Baby-sitters Club party with Ann M. Martin as guest and BSC freebies for ten friends - games, t-shirts, videos, autographed books and more. 2nd prize gets BSC games. 3rd prize gets BSC dolls.
- Little Sister Disney World Giveaway (LS #21) - Grand prize wins a 3-day trip to Disney World
- Little Sister Make-a-Wish Giveaway (LS SS#1) - 20 winners get their wish granted, up to $100 value
- BSC Mystery Giveaway (BSC Fan Club newsletter) - solve the puzzle to figure out what the next BSC Mystery title will be, and you could win a special hardcover edition of book #1 Kristy's Great Idea signed by author Ann M. Martin.
- Baby-sitters Club Snowbound Giveaway (book #50-51, SS#7) - Tell us who you would like to be snowbound with, and win a BSC snowbound kit, filled with a BSC backpack, sleeping bag, nightshirt, videos, and a board game.
- Super Special Trivia Giveaway (book #56-59) - Answer all 7 questions correctly, and you could be one of ten winners of a locket charm bracelet. 2nd prize is BSC portable cassette players, 3rd prize is carry cassette players.
- Winter Super Special Giveaway (book #60-62) - Enter to win a trip to Walt Disney World Resort
- Grand Prize - 5 day trip to Disney World Resort
- Second Prize (10) - Baby-sitters Club Record Album
- Third Prize (25) - Baby-sitters Club T-shirt
- Early entries (100)- BSC Calendar
- Little Sister Perfect Day Giveaway (LS #31-33) - Enter to be one of 4 Grand Prize winners of $250 for you and two best friends for your perfect day, plus 3 personalized "Three Musketeers" t-shirts for you and your two best friends.
- 20 Second Prize Winners receive 3 personalized "Three Musketeers" t-shirt
- Karen's Scavenger Hunt (LS #24-25) - Find all ten items in the picture, and you could win five of Karen's favorite things - roller skates, baseball hat, flashlight, backpack, teddy bear
- Baby-sitters Club Neat Boy Giveaway (BSC Fan Club newsletter) - Tell us about a neat boy you know, and you could win a BSC Nightshirt
- Baby-sitters Club Mini-Mystery Giveaway (BSC Fan Club newsletter) - Create your own BSC mystery - tell us what valuable object is missing, where the mystery takes place, which baby-sitter solves the mystery, and how. Win a Baby-sitters Club Fun Pack.
- Summer Super Special Giveaway (book #66-69) - Enter to win a 3-day trip to Universal Studios in Orlando, Florida. 25 second prize winners receive a Baby-sitters Club Fun Pack filled with a T-Shirt, "Songs for My Best Friends" cassette, BSC Stationery and more.
- Little Sister Summer Friendship Giveaway (LS #40-42) - Enter to be one of 500 winners receive a Baby-sitters Little Sister Stationery Kit with postcards, stickers, a pad, and a sparkle pen.
- Baby-sitters Club Look-Alikes (BSC Fan Club newsletter) - send us your photo which is a look-alike to one of the baby-sitters, and you could appear in an upcoming newsletter
- Get Involved Winter Challenge (book #70-73) - Write a one-page letter telling your plan to improve the town you live in and win a $10000 Scholarship savings bond, or one of two First Prizes of a book dedicated to you, your cause, and your community, a visit from Ann Martin, and BSC merchandise.
- The BSC Remembers Sweepstakes (book #77-78) - To celebrate 100 million books in print, enter to win:
- 10 Grand Prizes - $2500 cash prize toward any artistic, academic, or sports pursuit.
- 100 First Prizes - BSC videos, autographed editions of Ann M. Martin's upcoming holiday book, T-shirts, board games, and more.
- Name the Twins Contest (book #80-81) - Enter the first and last name of the new baby-sitter and her twin sister, and one lucky entry will be chosen to be featured in the series starting fall 1995, and the winner will have a future BSC book dedicated to her/him.
- Summer Sweeps (book #100) - Answer ten questions about the BSC, and you could win the Grand Prize of being featured in a future BSC story, complete wardrobe from LA Gear, BSC The Movie Video and soundtrack, BSC T-shirt, and The Complete Guide to The BSC book. 10 First prizes of a BSC T-shirt and an autographed Complete Guide to the BSC. 100 Runners-Up: a BSC T-shirt.
- California Diaries Getaway Sweepstakes (CD #1) - Fill out the coupon and win a grand prize of a 3-day trip to California, or 100 runners up will win a signed copy of California Diaries #3: Maggie.
- BSC Friends Forever New York City Getaway Sweepstakes (FF Everything Changes) - Win a trip to New York City with your best friend. Ann posted about the winner of this contest on her web site at scholastic.com.  Write a journal entry about you and your best friends (under 300 words), and you could win the Grand Prize of a New York City Getaway to visit Ann M. Martin, or 100 runners up will win a signed copy of Friends Forever #1 Kristy's Big News.