A bunch of things I think teacher librarians should unlearn:

1. That the little things really matter to those we serve and teach.  (For instance, whether or not we decide to shelve Mc and Mac together.)
2. That Boolean logic is the best search strategy since sliced bread.
3. That Wikipedia is bad or less-than-good in all contexts.
4. That databases are the only online sources with value.
5. That having a web presence, no–that having a really good and really useful web presence, is optional.
6. That someone else is exclusively or ultimately responsible for learning relating to information and communication and search technologies.
7. That the price initially quoted is the price you have to pay. (Thanks, Mom!)
8. That issues relating to Fair Use are generally going to be answered with the word no.
9. That no really means no when it comes to issues relating to access to the information and communication tools of today and intellectual freedom.
10. That libraries should be quiet.
11. That libraries should be neat.
12. That a library’s effectiveness and impact should be measured by the number of books it circulates.
13. That your stakeholders automatically will know what you contribute to your school’s culture.
14. That a library is merely a place to get stuff.
15. That your collection should be just-in-case rather than just-in-time.
16. That someone else is responsible for your professional development.
17. That ubiquity won’t change your practice profoundly.
18. That your library is bounded by four walls.
19. That your library is open from 8 AM to 3 PM.

Ooh... I like this list too! (see preceding post for another one)