Students often find the rebuttal speech, and other later speeches in the debate more difficult than the constructive speeches because the speeches require quickly responding to arguments the student has just heard. One way to make this easier is to prepare “blocks”.
A “block” is a prepared bit of speech that you can use in your rebuttal speech in response to an argument. (The name “block” comes form the idea of building a speech out of smaller parts in the same way you might build a house or tower out of blocks.)
If you have prepared both sides of a topic you can make reasonable guesses about what arguments the opponent will make. So you can prepare replies to them in advance. This means you don’t have to think up new arguments in the moment, you can use stuff you have already prepared.
Let’s say you are preparing to debate “The United Nations is no longer important.” You would start by looking at the sample cases and research, and think of arguments for both sides. Once you have thought about which arguments each team is likely to make, as well as writing the best versions you can for when you are debating that side, you can prepare blocks to reply to them.
For example, maybe you think that many Con teams will talk about the World Food Programme (WFP). You should then write a block responding to the arguments they’re likely to make.
Firstly, you might find some evidence of where the WFP is inefficient or has failed, and write the analysis and impact explaining that. Secondly, you could write out an argument that, even if the WFP is good, that doesn't mean the UN is important. Because any organisation that is given that much money could be equally successful, or better.
Notice here that one is attacking their warrant, by disagreeing that the WFP is effective, and the other is attacking their impact, linking the success of the WFP to the importance of the UN. This is often a good way to split up rebuttals, because it forces the opponent to defend in two ways at once.
When you are writing these responses you should write them just like any other argument in a debate. So include your claim, your warrant (why it is true, with evidence or analysis) and the impact (why this matters in the debate).
Remember that blocks are relevant to what your opponent’s argument. Avoid just hearing a particular key word, like “economy”, and then reading out a block that is generally about the economy but not relevant to what the other team actually said. This means that links and impact are even more important than normal, to make it clear to your judge why what you're saying is relevant.