About us

Inquisitive children are insatiable and want to understand everything exactly. TESSLOFF has been answering competently and comprehensively for more than 60 years in an easy to understand manner. Our products inspire to read on and spark interest in other exciting subjects as well.
TESSLOFF is one of Germany's leading children’s non-fiction publisher.



Ragnar Tessloff frequently visited the United States to purchase licences for comics. While there, he often visited bookshops taking special notice of the well-assorted specialised non-fiction book series for children and young people. This type of books was unknown in Germany. Ragnar Tessloff was enthusiastic – these books presented complex subjects to young readers in a concise, competent and comprehensible way. Having identified this market niche, he acquired the licence for the HOW & WHY fact book series.

The direct translation of the title was copyrighted in Germany so he decided to call the series WAS IST WAS. In autumn of 1961, the first WAS IST WAS issue was published – at first in form of a monthly magazine sold through newsstands. It was such a success that by 1963 it was published in form of a book.


WAS IST WAS became a synonym for youth fact books. After the original American series was discontinued in the seventies, German authors wrote the volumes within the scope of the regular updating, and the TESSLOFF VERLAG took over the series’ global rights.
The TESSLOFF VERLAG became the leading German publisher for children and youth fact books.

Our Programme

BOOKii - The intelligent audio pen

BOOKii brings books to life - for children and adults

By touching the texts or images with the pen, you can experience original sounds, listen to characters talk, play music, have texts read to you, or play video clips on a connected device (e.g. a smartphone) via an optional Bluetooth connection. Intuitive operation and the recording function make this appealing audio pen a whole lot of fun to use!

  • BOOKii encourages creativity and language fluency
  • Kids gain self-confidence by recording their own stories and listening to them again
  • Ideal for independent learning

WAS IST WAS - The Fascination of Knowledge

The most famous TESSLOFF product is WAS IST WAS – the leading international non-fiction children book series for children aged 8+. TESSLOFF is publishing the book series since 1961 and it became a synonym for youth fact books. Today the product world of WAS IST WAS comprises book series for very young children aged 3+ (WAS IST WAS Kindergarten), for young readers aged 4-7 (WAS IST WAS Junior) and the top selling series for curious readers aged 8+. WAS IST WAS presents topics that are prepared to be both age-based and exciting.

To match today's children's ways of enjoying knowledge transfer, that is to accommodate the different media use behaviour of our target group. Beside books the WAS IST WAS product world includes a wide variety of products: a TV and DVD, audio plays, e-books and apps as well as games and a magazine.

WAS IST WAS is available in more than 75 countries. Worldwide more than 77 million WAS IST WAS books have been sold.

WAS IST WAS First Reading

With its large fonts and clear layout, the new series WAS IST WAS – First Reading is an ideal introduction to independent reading. The main focus is on clarity and legibility of the texts. Info boxes, art illustrations and hotos all arouse young readers’ curiosity, making text familiarization easier.

Identification figures - such as Dolly the Dolphin or Edi the Alien - accompany the children on their reading adventures. An exciting quiz after each chapter, plus a final one at the end of the book, also ensure that the texts have been fully understood.

The little Major Tom

This is Tessloff’s new fiction series for children aged 7 and up! A curious little astronaut, his smart girlfriend and a clever Space Cat: Little Major Tom, Stella and Plutinchen take children along with them on their adventures in space and on earth. They repair the solar sail of their space station, fly through space, and observe a solar eclipse. Combining their strengths as a powerful team, they master every challenge.

Breathtaking, with lots of expertise and 15 volumes by now.

High-quality picture and board books

Books with a playful approach in knowledge transfer which are especially developed for babies and infants.

Colouring and activity books

Ever since the 1980s, TESSLOFF has also offered activity books for children of kindergarten and primary school age. These include coloring and sticker books.

Learning fun

Exercise books for children in kindergarten, pre-school and primary school that were developed by expert pedagogues following to the motto “Thus learning can be fun”.