We have recently started using QTI, specifically Uniqurate and QTIWorks, to write maths questions for delivery to students. Uniqurate can be used to write basic questions, including maths questions with numerical answers and simple randomisation of values. However, to incorporate more complex randomisation, e.g. randomising variable letters, to allow mathematical expressions to be given as answers and to do various other more complex things with maths questions, it is necessary to write (or, preferably, modify someone else’s!) QTI XML. This can get quite complicated and I have found some aspects of it difficult to get stuck into. I find that I know that something is possible, but it can take some time to pin down exactly how to do it, and I usually copy code from other questions. (Many thanks to Dr Sue Milne from ELandWeb for providing extensive help, both by giving access to her questions and answering many QTI-related queries)
One thing that I keep wishing for is a resource containing reusable blocks of QTI code that could be used to build a question. I believe that such a resource does not currently exist, so I have decided to start to write one, the links to which can be found below.
At this point I should make the disclaimer that I am still early on in my QTI journey, so I am no expert, and can by no means guarantee that this resource will be correct, but I will try to improve and extend it as I get to know the QTI specification better. The posts based on the XML snippets that I have been using, and therefore they are far from being a complete resourse. However, I hope they are useful to anyone getting started with QTI. Please feel free to suggest additions and corrections.