There is a children's song called "Klein Häschen wollt' spazieren gehn". And it's the first line of the song as well.
"Häschen" is a neuter noun, so shouldn't it be "Kleines Häschen" instead?
There is a children's song called "Klein Häschen wollt' spazieren gehn". And it's the first line of the song as well.
"Häschen" is a neuter noun, so shouldn't it be "Kleines Häschen" instead?
In today's standard German and with "klein" used as an adjective, you're completely right.
100 years ago, it was more common to use "klein" undeclined in this way, kind of an in-between between an adjective, a compound word part and a name part.
Note that the article is also missing: "Klein Häschen" is used like a name for a particular little hare here, it's different from "ein kleines Häschen" in that respect.
There was a series of jokes about a little girl "klein Erna", there is an old children's song with the lyrics "Hänschen klein / ging allein / in die weite Welt hinein...", there's the fictional stereotypical example of a small village called "Kleinkleckersdorf", and there are many real villages with a name starting with "Klein-".
So it's no surprise to find this in an old children's song.