Ask students to work in pairs or small groups. Give them a time limit to name as many vegetables as they can. One of my groups full of boys likes competitions so I set it as a competition.
Ask the group with the lowest number to read out their list and then ask other groups to add to it.
One of the vegetables on the list will surely be tomato, so here you can have students watch this interesting video that looks at a tomato as a fruit and have them think about this aspect.
Talk also about what they know about tomatoes.
Ask students if they know anything about cucumbers and what they are good for. Then show them this song:
The first time, I let the song play out until the end without interruptions. Later, if necessary, I stop the song and check understanding.
Ask groups to choose 1 vegetable from their list, do a short Google search about it and make a similar song about their chosen vegetable. They can easily find instrumental versions of popular songs on Youtube for the basis of their song. Alternatively, they can use one of many music apps to produce the music to it. One of my groups already had a guitar app installed on one of the phones so they produced the whole song from scratch.
Have groups perform the song while their schoolmates grade the performances. You can also make a video of the performances.
Have fun J