|Activity Type: Introduce, Build Accuracy|
|Activity Form: Standard|
|Grade: 4, 5|
|Group Size: Pairs or small groups|
|Length: 20-30 minutes|
|Materials: Using Prefixes Worksheet|
Using Prefixes Worksheet Answer Key
|Goal: Build vocabulary by understanding the meaning of the prefixes pre-, un-, and re-|
|Items: Content covered: Prefixes pre-, un- and re-|
 Steps to Follow
1. Display the following chart on the board. Do not fill in the column headings yet. You will add them together as you work through the activity.
|pre- (means "ahead of time" or "before"||un- (means "not")||re- (means "back" or "again")|
|pretest (test taken before studying to see what is already known)||unsure (not sure)||review (look back or look again)|
|prepay (pay before using or receiving something)||unprepared (not tested)||review (look back or look again)|
|preview (see part of something before seeing the whole thing)||unhappy (not happy)||return (turn back; give back)|
2. Focus on one column at a time and work on the definitions, writing them on the chart as students offer definitions in their own words. Encourage students to use their own experiences when telling what the words mean. Let’s look at the first column. Who can tell us what the word pretest means? Prepay? Preview?
3. After all the words in all the columns have been defined, challenge students. What is alike about all the words in column one? Column two? Column three?
4. Encourage students to see that each of the words in column one begins with pre- and that all the definitions are about something that happens before something else. Do the same for the other columns. Once you get agreement from the group, add headings to each of the columns.
5. Explain. Pre-, un-, and re- are called prefixes. A prefix is a word part at the beginning of a word that adds meaning to a word. When you know what a prefix means, it can help you figure out a word on your own even if you don’t know it already. A prefix is like a clue.
6. Add a word or two to each group. Examples: preteen, preschool, pregame, preseason, prewrite, preheat, prerecorded uncool, unfriendly, unable, unknown, uncomfortable, undo replay, rerecord, reread, redo, rewrite, reheat, repay, recount
Note that students may offer words that begin with the same letters but are not examples of the prefix—pretty or underneath, for example. Use these non-examples to reinforce the idea that a prefix adds meaning to the root or base word. –tty is not a root word, for example.
7. Have students complete the worksheet, Defining Words with Prefixes Pre-, Un-, and Re- and discuss results.
8. To extend the activity, have students work in pairs to think of words to add to each column. Allow them to use dictionaries if needed. Bring the group back together and let pairs share their words. Have one pair give a word and challenge the group to tell how the meaning of the prefix and the rest of the word combine to form the meaning of the whole word
9. For an extra challenge, ask students to write at least two sentences like those on Defining Words with Prefixes Pre- Un-, and Re- for their classmates to answer. This is not as simple as it may seem! Suggest that they begin with lists of words with the prefixes and words with the same letter strings. Dictionaries will also be helpful. Be sure students write answers on a separate piece of paper.
10. For English Language Learners, use the sentence frame, “_______ means _______” for oral practice with prefixed words. For example Unkind means not kind, or mean.
 About this Activity
This activity was contributed by Scientific Learning, http://www.scientificlearning.com
Only twenty prefixes account for 97% of prefixed words that appear in printed school English. Students benefit from learning the most common prefixes (Graves, 2004).