In order to be independent readers, students must understand 98% of what they are reading. When introducing a next text or concept, it is important to pre-teach key vocabulary.
I made up an example to illustrate. Read the sentence below and see how much you understand.
Emma sought a quiet phrontistery in the abaft. She felt a sense of the acatalepsy regarding the situation in which she found herself.
So… How did you do? Were you able to use context to understand the vocabulary? I am guessing context would not be enough, even if these sentences are embedded in a larger paragraph.
We put our students in the same situation. We encourage them to use the pictures and the context (great strategies), but often, they also need to be taught the words.
Here is the translation using a simpler vocabulary:
Emma sought a quiet place to think at the back of the ship. She felt a sense of uncertainty regarding the situation in which she found herself.
I hope this illustration helps to convey the importance of pre-teaching vocabulary!