This activity requires almost no special material. All you need are many small pieces of paper (just get some scrap paper and cut it into 8s or 10s) and 5-6 containers. You can use bags, envelopes, Tupperware container, anything that makes it easy for you to draw the pieces of paper from.
1) Split the class into 5-6 groups
2) Give each group a stack of the cut-up papers
3) Assign each group a category. I used food, animals, vehicles, people/characters. 1-2 groups will do adjectives.
4) Have the students write as many words as they can think of for their category, one word per piece of paper. I usually give them about 5-10 minutes, depending on their level of English.
5) Once they are done, take the pieces of paper, and put them into a container for each category.
6) Now the fun begins. You start by randomly drawing an adjective, and then depending on the adjective you draw two nouns. The reason I do this is because some adjectives don't really make sense for certain nouns. For example, if you draw the adjective "sweet", then you'd want to draw from the Food category and not Vehicles.
7) Once you have three words, ask the students to make a comparative sentence using the words. You can put the sentence up on a PowerPoint screen or write on the blackboard, and just change the new words as you go.
This is a simple game that lets the students practice comparatives, and also vocabulary. It's especially fun when you draw something silly like Naruto, Son Goku, and cute.
I use stamp sheet so I usually make it so the fastest group that can make a sentence gets a point, and top 2 groups at the end get stamps. If you find one group is more quiet or one group is dominating the others, then just go around in order so all groups get a chance.