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EJ12 Girl Hero #1
Hot & Cold
EJ12 Girl Hero is Australia's bestselling adventure series for young girls!
The heat is on as someone seems to be melting the polar ice cap.
Special Agent EJ12 needs to crack the codes and keep her cool to put the evil-doer’s plan back on ice. That’s the easy part. As EJ12, Emma Jacks can do anything. So why can’t she handle the school Ice Queen of Mean, Nema? Perhaps she can after all.
Susannah McFarlane is the author and creator of the popular EJ12 Girl Hero series, the co-author of the best-selling Boy vs Beast series, and the author of the delightful Little Mates series of books.
The heat is on as someone seems to be melting the polar ice cap.
Special Agent EJ12 needs to crack the codes and keep her cool to put the evil-doer’s plan back on ice. That’s the easy part. As EJ12, Emma Jacks can do anything. So why can’t she handle the school Ice Queen of Mean, Nema? Perhaps she can after all.
Susannah McFarlane is the author and creator of the popular EJ12 Girl Hero series, the co-author of the best-selling Boy vs Beast series, and the author of the delightful Little Mates series of books.
96 pages, Kindle Edition
First published January 1, 2010
40 people are currently reading
265 people want to read
About the author
Susannah McFarlane
132 books68 followersSusannah McFarlane is a successful children’s book author who, after many years working as a publisher, now spends her time writing and creating stories that kids love to read.
She is the creator and writer of the awarding-winning EJ12 Girl Hero series, the creator and co-author of the hugely popular series for boys, Boy vs Beast, and the author of the Little Mates series of alphabet books for under fives.
Susannah, who was also the original concept creator of two of Australia’s leading tween fiction series Go Girl! and Zac Power, understands kids and loves creating stories they enjoy to read. Her understanding and belief in the need for age-appropriate but fun content for kids comes from over twenty years experience as a children’s book publisher and from having worked with some of the world’s leading brands and writers. Susannah actually counts Thomas the Tank Engine, Winnie the Pooh, Tintin, and Enid Blyton as friends, not just former colleagues!
Susannah is also the founding director of Lemonfizz Media, a boutique children’s publisher that focuses on developing a small number of publishing projects across all content platforms, and a speaker on children’s publishing for the RMIT Editing and Publishing course.
She was previously the managing director of Egmont Books UK; the vice-president of the Egmont Group; the co‐owner, managing director and publisher of Hardie Grant Egmont; a contributor to the UK trade journal Publishing News; and the Convenor of the Children’s Publishing Committee and Board Director of the Australian Publishers’ Association.
She is the creator and writer of the awarding-winning EJ12 Girl Hero series, the creator and co-author of the hugely popular series for boys, Boy vs Beast, and the author of the Little Mates series of alphabet books for under fives.
Susannah, who was also the original concept creator of two of Australia’s leading tween fiction series Go Girl! and Zac Power, understands kids and loves creating stories they enjoy to read. Her understanding and belief in the need for age-appropriate but fun content for kids comes from over twenty years experience as a children’s book publisher and from having worked with some of the world’s leading brands and writers. Susannah actually counts Thomas the Tank Engine, Winnie the Pooh, Tintin, and Enid Blyton as friends, not just former colleagues!
Susannah is also the founding director of Lemonfizz Media, a boutique children’s publisher that focuses on developing a small number of publishing projects across all content platforms, and a speaker on children’s publishing for the RMIT Editing and Publishing course.
She was previously the managing director of Egmont Books UK; the vice-president of the Egmont Group; the co‐owner, managing director and publisher of Hardie Grant Egmont; a contributor to the UK trade journal Publishing News; and the Convenor of the Children’s Publishing Committee and Board Director of the Australian Publishers’ Association.
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Displaying 1 - 30 of 51 reviews
April 20, 2012
I liked the premise of this story - Primary School girl who doubles as a spy for a secret agency and goes on a series of adventures. The things she finds difficult to do at school - like facing down bullies - becomes easier after a mission from SHINE agency which inevitably teaches her the skills she needs to solve her real life problems (this theme persists throughout the series).
It was a very quick and easy read full of well-integrated facts (about Antarctica in this case), positive environmental messages and experiences that young primary school girls can probably relate to.
The codes are very simple in this first book, but they get progressively harder and each code is presented on a different page to the solution, giving the reader a chance to work it out for themselves before turning the page.
EJ12 is a very light, friendly read with none of the 'grit' or 'darkness' which has been creeping into other child spy books of late. All about saving animals, and the world, from SHADOW's 'dastardly plans', I found myself wondering in a couple of places if it was actually a spoof, but I suspect that for the target age group (about 7 - 10), it would go down quite well.
It was a very quick and easy read full of well-integrated facts (about Antarctica in this case), positive environmental messages and experiences that young primary school girls can probably relate to.
The codes are very simple in this first book, but they get progressively harder and each code is presented on a different page to the solution, giving the reader a chance to work it out for themselves before turning the page.
EJ12 is a very light, friendly read with none of the 'grit' or 'darkness' which has been creeping into other child spy books of late. All about saving animals, and the world, from SHADOW's 'dastardly plans', I found myself wondering in a couple of places if it was actually a spoof, but I suspect that for the target age group (about 7 - 10), it would go down quite well.
April 7, 2014
When I was 9, I loved these books. I was always getting the next ones and I would finish them quite quickly (for a 9 year old). I always really admired EJ's character and tried to solve the little puzzles in my head before she could. I really liked reading through what she was going through and the different ways she shows her integrity. I think these books are great, probably for younger girls.
November 19, 2016
There are no horses in this book... it's awesome!!
January 1, 2013
A good little read, perfect for its intended audience, which was my 8 year old. Lots of action with a few good puzzles along the way. She enjoyed it very much.
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August 28, 2015A girl who likes math and puzzles. That seems like a rarity. Emma Jacks may be having mean girl trouble at school, but as a secret agent EJ12 she figures out how to handle people like that.
This was a really fun adventure as EJ goes off to the Arctic to stop an villain from melting the polar ice cap to sell for water. There’s some friendship difficulties too that Emma figures out how to manage and does so beautifully at the end of the book. Lots of action, fun gadgets, a secret identity and puzzles. Emma has to solve a bunch of puzzles in her mission and they’re included in the story so the reader can try their hand at them too. Perfect for third and fourth grade.
This was a really fun adventure as EJ goes off to the Arctic to stop an villain from melting the polar ice cap to sell for water. There’s some friendship difficulties too that Emma figures out how to manage and does so beautifully at the end of the book. Lots of action, fun gadgets, a secret identity and puzzles. Emma has to solve a bunch of puzzles in her mission and they’re included in the story so the reader can try their hand at them too. Perfect for third and fourth grade.
August 12, 2017
This was a really sweet, quick read. Obviously quick, as it's written for kids. I would highly recommend it for kids who want to feel empowered. It was a sweet story of Emma Jacks who seems to be a typical elementary school student, complete with best friends and bullies. But what you soon find out is that she's actually a secret agent for SHINE, which works to fight the evil agency SHADOW. Emma had to be quick-thinking, adaptable, and brave, in her mission work as well as her everyday life. I think it's great for kids ages 7-10, and the best part is it's part of a series. Plus it had some need little facts strewn throughout about the South Pole that I'd never heard before!
October 26, 2021
Hot and cold is about a girl who won a math contest and turned into a secret agent. This is her first mission and she saved the world by making sure the polar ice caps didn’t melt. A lady turned the polar ice caps into polar ice taps, or she tried to at least. But EJ saved the world by making sure she didn’t melt it into water. I really liked the book.
Kaylyn (age 8)
Kaylyn (age 8)
September 11, 2011
Its great !!!!!
September 11, 2011
cool books! they are like for young and old kids! it gives a bit of a passsion!
January 13, 2012
A great girls spy book. Loads of action and fun.
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September 25, 2012cool ice cool :)
Read
March 10, 2013This book is so cool
March 16, 2014
I liked the genre of this book, and it kept me interested (as spy work is always pretty cool).
December 8, 2021
Emma jacks was an ordinary girl at school. She didn't like the way Nema treated her friends Elle and Hannah. She was mean, but instead of standing up to her, she froze, and let mean Nema say horrible things.
Luckily Emma Jacks was also EJ12 Special Agent for SHINE and she was called on to go on another secret mission. This time she de-coded her first message they'd intercepted by SHADOW, but she didn't understand what it meant. Part of the message revealed her destination and the ice-cold scientist Dr Catrina Hill, who was in Antarctica. Was she the cause of the environmental issues that were happening? EJ12 was sent to solve the next code and confront the scientist.
When Emma returned to school she'd had learned a lot during her mission as EJ12. Now she could face up to Nema and appreciate her friendship with Elle and Hannah.
Luckily Emma Jacks was also EJ12 Special Agent for SHINE and she was called on to go on another secret mission. This time she de-coded her first message they'd intercepted by SHADOW, but she didn't understand what it meant. Part of the message revealed her destination and the ice-cold scientist Dr Catrina Hill, who was in Antarctica. Was she the cause of the environmental issues that were happening? EJ12 was sent to solve the next code and confront the scientist.
When Emma returned to school she'd had learned a lot during her mission as EJ12. Now she could face up to Nema and appreciate her friendship with Elle and Hannah.
July 24, 2025
I first read the EJ12 series when I was around 10 years old and it instantly captured my imagination, especially since Spy Kids (2001) was my favourite movie growing up. EJ12 felt like the perfect blend of everyday schoolgirl and secret agent, which was exactly who I wanted to be at that age.
The book is fast-paced and easy to read, with just enough action and mystery to keep young readers hooked. While some parts are predictable, it’s still a fantastic introduction to middle-grade fiction.
The book is fast-paced and easy to read, with just enough action and mystery to keep young readers hooked. While some parts are predictable, it’s still a fantastic introduction to middle-grade fiction.
March 30, 2019
This is an Usborne book that I received with the kit. I wanted to check it out for my kids. I wanted to like it, the idea of it was interesting. But I didn’t really like it, it was kind of simplistic and how it dealt with problems. The problems/obstacles were instantly solved with a click or impossible mind read. I know that I am not the target audience, but I didn’t like it.
December 17, 2024
Life has felt a little heavy lately, so revisiting a childhood favorite has been incredibly comforting. I was obsessed with this series as a kid and first read Hot and Cold when I was 8 (now 22). It’s just as good as I remember. It’s a very easy read, which makes it a great way to bump up my reading count for the year 🤫—nostalgic and joyful in equal measure.
May 12, 2018
hi this is 2018 14 year old me who remembers that 8 year old me loved this book so,,,,,yeet
(i'm going to repeat this statement for literally every book i add to my children's literature shelf okay)
(i'm going to repeat this statement for literally every book i add to my children's literature shelf okay)
March 9, 2017
EJ12 i 1 off my favourit sirees but why is she afrade off evry thing??
goddamn weekling kid (_0 - 0_)
goddamn weekling kid (_0 - 0_)
July 4, 2017
really short but a nice story lol, actually it was a bit boring.
March 26, 2018
Sooooo good. Very adventurous and a must read more kind of book.
April 20, 2020
👍 G R E A T. B O O K.
May 20, 2020
I love it when it was her birthday
October 6, 2020
I liked EJ12 because of how EJ was just a normal girl until she found the spy agency. I also really liked the special missions that she was sent on.
May 11, 2021
EJ12 was my favourite series all throughout years 2, 3 and 4. I always wanted to be like EJ - to go on special missions and travel around the world!
Beginning to reread the series (a number of years later - and partially to bump up my reading challenge shhhhhh) was a huge trip down memory lane <3 I remember that feeling of trying to crack the codes and willing EJ to succeed.
Of course I already knew what happens in the story, and there is some plot convenience that is only evident to me now as a much older reader.
But for the target audience, I’d say the series is perfect!
Beginning to reread the series (a number of years later - and partially to bump up my reading challenge shhhhhh) was a huge trip down memory lane <3 I remember that feeling of trying to crack the codes and willing EJ to succeed.
Of course I already knew what happens in the story, and there is some plot convenience that is only evident to me now as a much older reader.
But for the target audience, I’d say the series is perfect!
July 14, 2021
I'm in love with this series. They are all so cool and amazing. I still wish there were some more pictures.
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January 5, 2023these books are so slay younger me had taste. also why do i kinda have a crush on dr hill like yeah sure she’s the villain but girl is hot. anyways gonna binge read the rest of the series.
April 25, 2023
i dont care what you say this counts
Displaying 1 - 30 of 51 reviews