Individual investigation

This section contains information and resources relating to the IA as it will be implemented from 2014. Just to make this clear, that means students who begin the IB in August 2014 will be doing this new IA, students who have already started the IB will continue with the old system.

In a nutshell, from 2014 students will be required to complete only one piece internally assessed of practical work. This will be in the form of an investigation of 6 - 12 pages length which should take no more than 10 hours. In terms of words it's around 2,000 so half as long as an extended essay. This doesn't mean that they will only do one piece of practical work but only one will be assessed, the rest of the 50 hours (HL) will be 10 hours of group 4 project (same as before) and 40 hours of non assessed lab work which should include 10 required experiments that will be tested on paper 3.

It takes time to adapt all the old worksheets to the new system but so far I have completed:

  • A beginners guide to IB practical work.
  • Details on how to apply the new criteria.
  • Logistics of how to implement the programme.
  • Suggestions of topics for student investigations.
  • Suggested ways of carrying out the required labs and preparing for paper 3 questions.
  • Example results.
  • Details of how to scaffold skills needed to perform an investigation.
  • advice for students on how to write a good investigation.

Since this is all very new I have no student work to draw upon so am doing all the sample investigations myself, this takes time but gives a good inside view of what it is like to do a 10 hour investigation. So far I have written the following investigations:

Measuring e/m

The Lens makers equation

Trajectory of a balloon

Note: I will be using a lot of the old DCP practicals to scaffold skills and reinforce theory. Since these will no longer be assessed, I will give my students full details on how to process data and some hints as to what to look for in the conclusion and evaluation. This information should not be given to the second year students who might be submitting the same lab for assessment.


Starting with students starting the IB diploma in 2014 the only piece of assessed practical work will be the investigation. This is a 10 hour study of 6 - 12 pages in length. Ideally the students will come up with heir own topic and research question but this will probably be beyond a good number of students so we must be ready with some prompts, advice and in the last resort suggestions.

10 hours

My first reaction to the new proposal was "how is a lab going to last 10 hours"? Most of my students like to be finished with measurements as quickly as possible, especially if the class is before lunch. There aren't many labs on my 4psow that would stretch to 10 hours even design labs don't last that long. The misconception here is that the 10 hours is for hands on lab work, it isn't. In the pre 2014 IA model we were only allowed to count actual lab hours on the psow, not the time taken for analysing data and writing the report. The new subject guide makes it clear that this is not the case with the investigation, you can count the time to explain the process and assessment criteria as well as time used to advise the students in class. So, I should spend 10 hours of class time but that that time does not have to be the time spent taking measurements. Thank goodness for that,10 hours is more time than the average EE writer spends in the lab. This makes it seem much less intimidating, including time to write the report, a conscientious student could easily spend 10 hours writing a "design lab" so this time frame is not something we are unfamiliar with.

6-12 pages

This is a wide range and I'm going to advise my students to keep it short, in the 6 - 8 region. When first confronted with the idea of 10 hour investigations in physics a lot of teachers thought - mini extended essay. 12 pages with 10 hours of labwork isn't a mini EE it's a full blown one. The investigation is supposed to be focused and its easier to keep focus for 6 pages than 12 so in this case more is in fact less. There is no penalty for writing under 6 pages but it might be diffciult to get full marks in all categories if the report is too short. A good "design lab" with a full conclusion can easily run to 6 or 8 pages so we are not talking about anything so very different to the sort of thing we have been doing for years, the difference is mainly in the assessment criteria.

Why the Change?

One of the driving forces behind the changes to IA was to enable a wider variety of labs to be assessed. The old system worked but it encouraged a checklist approach. The criteria clarifications published on the OCC made it clear that there were certain features required to gain a full score but there were also some problems (in my opinion).
The linear problem
To gain a complete in aspect 3 of DCP a best fit line plus lines with max and min gradients to determine the uncertainty in the slope was required . This meant that many good design labs could not score well in DCP since they didn't give linear relationships. The way around this was to do a set of separate DCP labs giving students the chance to score high marks on more straight forward experiments.
The justified conclusion problem
To justify a conclusion and fully evaluate results it is necessary to have a good understanding of the underlying theory this is very difficult to do well on a self designed experiment with theory that is way beyond the comprehension of even the best student or his/her teacher. Again, the way around this is to include some practicals in your schedule that are based on understandable theory.
The range and repeats problem
To score 2 in aspect 3 of the design criteria all you had to do was quote a reasonable range and say that you plan to repeat your measurements (if applicable). Maybe it was a bit easy to tick the box here. Personally I never gave full marks unless the student had actually collected the data but this wan't really a requirement.
Simulated experiments
This wasn't a problem for me since I never wanted to do completely simulated experiments but it is a problem if the IB want to implement an online physics course (and they do). The old IA made it quite difficult to gain a good score without collecting real data. How would you estimate uncertainties and compare with accepted values etc. How can you design an experiment without any apparatus? (Actually I think you can do quite good experiments with very little apparatus but anyway...)

So, in a nutshell the IB have loosened up the criteria so they can be applied to a much wider range of investigations

Selected Pages


Analysis of marks 18 January 2016

After a couple of months there have been 18 responses but 3 of these were blank so only 15 sets of marks. This is not enough...


Ideas for investigations 29 May 2014

These are all starting points for investigations, the idea being that a student would focus on a piece of apparatus, find...


ICT 12 May 2010

Three years ago I was asked by the subject area manager for physics to make a website specifically to help IB physics teachers...

Preparation tasks: Design Labs 28 November 2018

One way of starting the investigation process as followsThe starting point is the same as used in the "design labs" of the...

Beginners guide 1 August 2018

From 2014 practical skills will be assessed in two different ways, the internally assessed (and externally moderated) investigation...

Moderation 30 January 2016

The purpose of moderation is to ensure that there is some consistency between teachers in different schools. Moderators...

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