Word-replacement teaching texts?

[UDUT, KENNETH]

Hello again SEELANGers.  My apologies for continuing to clutter up
mailboxes around the globe.

I have heard of a teaching-text which works in this manner:

A story is presented, in the native tongue of the learner.  A few words
are changed into the target language, very minimally.  As the story
progresses, more and more words from the target language are inserted
(with definitions on the bottom of the page of course), until by the end
of the book, the text is entirely in the target language.

I believe the group producing these texts were from Norway, or perhaps
Sweden.

Can anyone corroborate what I've heard?  Do texts like these still
exist?  Have they been shown to be useful, or detrimental?

Thanks in advance for any information you can provide.


-Kenneth
kenneth.udut at spcorp.com