Show a picture/video on the WB. What do you see in the pictures? What is strange in these pictures? Talk with your partner for 2 minutes. Listen to some of the Ss' ideas.

Start eliciting the meaning of the vocabulary that needs to be pre-taught. optical illusion Is it something that we see or hear?-See Does it trick the mind? - Yes Do we think is real?- Yes Is it real? –No rod Show them a picture of a rod and iintroduce the Ss with the word. criss-crossed, curvy lines, parallel lines Show the Ss three pictures and three pieces of paper with each phrase written on them. Each picture has a design of one of the patterns above. Take the phrase parallel lines and I ask the WC in which picture this phrase fits. If they have difficulty in responding to it, I will try another phrase. In case I cannot elicit the meaning from the Ss I will match the phrases to pictures.

Give Ss a text about optical illusions. Tell Ss to read individually and find and underline the answers to these two questions: They have 4 minutes for that. 1. How is an optical illusion made? 2. What sort of people have been interested in them? ICQs: Are you working alone or with your partner? Alone Are you going to write or underline the answers? Underline How much time do you have? - 4 minutes Check their answers with their partner. WCFB follows for justification. As for the next step of this stage, divide Ss in groups of three and give each group a set of phrases and words related to optical illusions and four pictures of optical illusions, the ones that are on the Global Coursebook (The hermann Grid, Zollner'sillusion, Schroeder's staircase, The impossible object). They have 4 minutes to match the words/phrases to the pictures.. For checking groups stand up and check each other's matching. Then an Answer Key is given to them.

Divide Ss into two groups (possibly do some regrouping). Instructions: "Group No1 leaves the classroom and group No2 stays in the classroom. I will give each one of you two pictures and you will listen to the descriptions of two famous optical illusions. You will have to find out which picture matches the description.You will work alone and you will have 4 minutes for that." Now ask group No1 to leave the classroom until I call them back. The group that stays in the classroom will listen to a half of a recording and completes the task. They check their answers with their partner. WCFB follows up. Ask if there are any questions. Then, this group leaves the classroom and the other group comes in and follows the exact same procedure but they listen to two different descriptions and they have two different pictures. They have 4 minutes and they work individually. Check their answers with their partner.WCFB follows up. Ask if they are any questions.

The whole class is in the classroom. Tell Ss that they are going to listen to the recording again. This time they will have to listen carefully because each group will have to explain to the other group how each of the two illusions work . They will have the two pictures in front of them. Group No1 leaves the classroom and the listening task for Group No2 starts. Then Group N01 follows and Group No2 leaves the classroom. Then the Ss are all in the classroom and each group explains the illusions they had to the Ss of the other group. WCFB and check if the Ss have understood the illusions. The transcript of the recording will be given to them.

Divide Ss into groups of three (possible do regrouping). Give each group one picture of optical illusion. They will talk to each other about the picture they see using the vocabulary that is related to optical illusions. They have 5 minutes for that. The first group that is ready will present its picture to the whole class. Task Feedback and error correction will follow up.