It is important that children build up a vocabulary with which to talk about fractions. Of course this is a gradual process, but greatly helped by you modeling appropriate language wherever possible and drawing attention to good use of specific vocabulary by children themselves. You could encourage children to write a class definition for your 'working wall' and see if this can be improved on over the time spent on fractions. The articleDeveloping a Classroom Culture That Supports A Problem-solving Approach to Mathematics offers several practical ideas to help your classroom become a classroom that is based on talk.