Many schools attach great importance to their choice of a graded reading scheme, and all modern reading schemes have coloured illustrations, and some of them a great diversity of supportive story books, class, group and individual didactic material and apparatus, including discs and filmstrips. Some schemes are constructed either as Look and Say or Phonic, whereas others claim to be useful to teachers using either method. The teacher must select with care and not confuse books based on a Look and Say approach with those written for a Phonic method. The advantages of a Look and Say approach means that there is no restriction on vocabulary—and any word within the children's passive or active vocabulary can be presented. Many children are taught to read without a graded reading scheme or by using books from several schemes.