From Kirkus Reviews

Matt and his two friends get the chance to travel back in time to 1951 so he can try to help his grandfather become a major league baseball player. Grandpa Joe was ready to join the New York Giants when he hurt his leg dancing. Now he trains 12-year old Matt to pitch but still regrets missing his chance. Happily, the librarian at Matt's middle school, a nice but quirky lady, turns out to be a time traveler, and she helps Matt and his friends Luis and Grace travel back to July 4, 1951, to attend Uncle Alex's party and try to save Grandpa Joe. Once there, the children are amazed by the different styles and the awful green gelatin mold that nobody wants to eat. But Grandpa Joe turns out to be at a double header in Ebbets Field, and Matt cannot resist the opportunity to see the historic baseball park and to watch heroes Jackie Robinson and Willie Mays play. Concerns about meddling with time emerge: if they can save Grandpa Joe from his accident, will that cause something much worse to happen? And will the children make it back to the present or be stuck forever in the past? Slapstick moments abound, but the focus remains mostly on Matt's wonder at seeing his grandpa as a young man and actually being present at Ebbets Field. Matt and Grace are white; Luis is Latino. This series kickoff is a pleasant glimpse of popular history for graduates of the Magic Tree House. (Science fiction. 8-12)

– Kirkus Reviews

School Library Journal

A whirlwind, humorous adventure of three middle school students who travel back in time with the help of their librarian. Matt and his friends, Luis and Grace, notice some odd things in their school library—Albert Einstein pops up, Vikings storm the bookcases, and Jackie Robinson tosses a ball in the corner. The librarian, Ms. Tremt, dismisses each strange occurrence with a laugh and a casual comment. The trio soon find the Book of Memories and realize that it is actually a time travel portal. Matt decides to travel back to the summer of 1951 and learn about the accident that prevented his grandpa from becoming a major league baseball player. Most of all, he wants to know why Grandpa says,“Because of the accident, I met the girl I was going to marry, so it was all worth it.” Should Matt try to change the past and ensure that his grandpa gets to play in the major leagues? Though the characters are in middle school, the ideal audience for this light and funny adventure is mid-elementary students. VERDICT Hand this fun new series starter to chapter book readers who have outgrown the “Magic Treehouse” books.

– School Library Journal

Booklist

Ever wish you could change history? Twelve-year-old Matt wishes he could go back to 1951 to keep his Grandpa Joe from falling into a swimming pool at a party, thus injuring his ankle and missing his opportunity to play baseball for the New York Giants. For Matt, this is just wishful thinking, but his middle-school librarian, Valerie Tremt, may have the solution. She happens to be a time traveler, as her anagrammed name suggests. She gives Matt and his best friends, Grace and Luis, The Book of Memories, which gives them the ability to travel back in time, but they have only three hours to change the events of the pool party. Minutes before their time is up, they must correct a small but crucial historical detail. Lots of dialogue and fast-paced action are crammed into the three-hour time frame, making this first book in the In Due Time series, by author Nicholas O. Time (aka Sheila Sweeny Higginson), a hit for reluctant readers or those after an armchair adventure.

— J. B. Petty

– J.B. Petty, Booklist