Forms of interviews
Interviews can take several forms.
Clinical interviews are situations where the interviewer assesses if the student can solve the problems independently.
Affirmation of answers, encouragement and suggestions for solution are not usually offered, although students are asked to elaborate on their responses.
Teaching interview protocols are less formal with the aim of supporting the student to reveal their thinking and strategies.
In these situations the interviewer may:
- offer praise, encouragement and affirmation
- make suggestions when students are stuck
- ask for justification to gain better insight into the student's thinking
- encourage reflection if answers or strategies are unclear or not valid.
Other features of interviews that assess mental computation can be altered.
In think-aloud interviews, students talk through a problem as they try to solve it on the spot. This form is useful as it usually reveals students’ initial preferences.
Rehearsed interviews are those in which the student sees the problems before the interview and has the opportunity to solve the problems beforehand. This form is less stressful for students but sometimes students alter their initial strategy upon reflection, so their first-up thinking remains hidden.
Access to paper or calculator may seem a strange variable for an interview on mental computation.
The positive feature of allowing access to recording is that solutions that may not be possible for the student, due to memory load or missing knowledge, are revealed.
The negative feature is that many students interpret access as an expectation that they will use written calculation or the technology.
Calculators change the affordances in a problem and this can prove counterproductive to revealing mental computation strategies.
Sources of good questions
Many internet sites and books offer well-researched questions that can be used to assess mental calculation.
Revealing student thinking during interviews requires questioning that prompts the student to talk about their mental calculation strategies. Wait time, balancing neutrality and intervention, asking appropriate questions, and recording responses make interviews challenging.