AWARDs and nominations
H.C. Andersen Honour List Diploma for About a Boy (Poika)
1989
Nominated for Topelius Prize for Talking Dog (Puhuva koira)
1990
Artist of the Year Award by Keskisuomalainen Newspaper
1990
Artist of the Year Award by Province of Central Finland
1991
IBBY Honours List
1992
Nominated for Topelius Prize for Little Brothers and the Magic Key (Pikkuveljet ja taika-avain)
1993
Arvid Lydecken Prize for Ella & Friends on a Class Trip (Ella luokkaretkellä)
1997
H.C. Andersen Honour List Diploma for Ella & Friends on a Class Trip (Ella luokkaretkellä)
1997
Shortlisted for Finlandia Prize for the Best Children’s and Young Adult Book for Ansa and Oiva (Ansa ja Oiva)
1999
IBBY Honours List
2000
Kaarina Helakisa Prize for Exceptional Merits as an Author
2005
SSKK Book Club Prize for Exceptional Merits as an Author
2005
Plättä Prize for Ella & Friends: Superstar (Ella ja Paterock)
2005
Finlandia Prize for the Best Children’s and Young Adult Book for The Seesaw (Keinulauta)
2006
Topelius Prize for Fireblade (Guardians of Sampo, Part 1) (Sammon vartijat 1: Tuliterä)
2007
WSOY Literary Foundation Reward for his Exceptional Merits as an Author
2009
Plättä Prize for Ella & Friends Hit the Jackpot (Ella ja jättipotti)
2008
WSOY Literary Foundation Prize for Exceptional Merits as an Author Koura Prize for the TV series script ‘Taivaan tulet’
2008
Finnish Kalevala Society Foundation Prize for the Guardians of Sampo -series (Sammon vartijat 1–3)
2010
Stavangerin kirjasto, book of year for the Ella og andre
2010
Laivakello Prize for Exceptional Merits as an Author
2011
Plättä Prize for for Ella & Friends: The Lost Pointer (Ella ja kadonnut karttakeppi)
2013
Nominated for Astrid Lindgren Memorial Award (ALMA)
2013
Suomi Prize; The Finnish Culture Prize awarded by the Ministry of Culture and Education
2014
Nominated for Astrid Lindgren Memorial Award (ALMA)
2015
Nominated for the Arvid Lydecken Prize for Invitation
(Kepler62 – Book 1 , co-authored with Bjørn Sortland) (Kepler62 – Kirja 1: Kutsu)
2015
Nominated for the ARK Children’s Book Prize (Norway) for The Countdown
(Kepler62, Book 2, co-authored with Bjørn Sortland) (Kepler62 - Kirja 2: Lähtölaskenta)
2015
Children's Rights Influencer Award by UNICEF Finland
2016
Runeberg Junior Prize for Pete’s Fishing Book (Paten kalastuskirja)
2017
Lese-Kick Award (Germany) for Pete’s Football Book (Paten jalkapallokirja)
2017
Pro Finlandia Medal (The Order of the Lion of Finland) awarded by the President of Finland
2019
Nominated for the Arvid Lydecken Prize for The Whisperer’s Lair (Kepler62 – New World 3) (Kepler62 – Uusi maailma 3: Kuiskaajien kaupunki)
2019
Leipzig Lesekompass Prize (Germany) for The Invitation
(Kepler62, Book 1, co-authored with Bjørn Sortland) (Kepler62 - Kirja 1: Kutsu)
2020
Hea Lasteraamat (Estonia) for The Jingle Bell (Shadows 1) (Varjot 1: Helähdys)
2020
Nominated for the Arvid Lydecken Prize for The Jingle Bell (Shadows 1) (Varjot 1: Helähdys)
2020
Nominated for the Arvid Lydecken Prize for The Jingle Bell, Book 1 of The Shadows Trilogy (Varjot 1: Helähdys)
2021
Shortlisted for the Finlandia Prize for Kepler62 – Terra: The Clones (Kepler62 – Terra: Kloonit)
2021
Shortlisted for the Hans Christian Andersen Award
2022