The SQA Higher Biology assignment: candidate guide, marking instructions and how to score 18 out of 20

The Higher Biology assignment is worth 20 of your 120 course marks, which is a sixth of your grade. It is also the part of the course where the marking instructions are published in advance and the marks are almost entirely predictable. Treated properly, it is the easiest A grade insurance you will ever get.

01What the assignment is

You research a biology topic with an underlying issue, carry out or use experimental work, and then write a report under exam conditions in a single session, using only the research notes you are allowed to take in. Your teacher cannot help you during the write up. The report is sent to the SQA and marked externally against published criteria.

02Choosing a topic that scores

The topic decides your ceiling. A good assignment topic has three features.

It has a clear underlying biological issue with two sides you can discuss. Antibiotic resistance, GM crops, biological versus chemical pest control, the effect of exercise on lactate, and enzyme activity under different conditions are all reliable choices.

It allows you to gather your own numerical experimental data with a variable you control and a variable you measure. Qualitative topics look interesting and are very hard to score highly on.

It has good published data available so your second source of information is real, comparable, and citeable.

If you cannot draw a line graph from your own results and compare it with a published graph, the topic is wrong.

03Where the 20 marks sit

The exact allocation is published in the SQA marking instructions, but the shape is consistent, and it is worth knowing before you start rather than after.

Aim and underlying biology. You get marks for stating a clear, specific aim and for a relevant, accurate account of the underlying biology at Higher level or beyond. This section is written from your research notes, so there is no reason for it to be anything other than excellent. Depth matters more than breadth: explain the biology that your experiment actually tests, not everything you know.

Data collection and handling. Marks for describing your method in enough detail that it could be repeated, for the raw data being presented in a correctly formatted table with units and headings, and for processing that data correctly, usually as averages, percentages or ratios.

Graphical presentation. This is where marks are lost most reliably. Correct choice of graph type, both axes labelled with units, a suitable scale, accurately plotted points, and a title. Every one of those is a checklist item and every one is a mark. Practise drawing your graph before the write up day.

Analysis and conclusion. A conclusion that answers the aim, in the same terms as the aim, supported by the data you collected. Not a summary of what you did. Not a general statement about the topic.

Evaluation. Marks for valid evaluative points about your procedure, each one linked to why it affected reliability or validity, and each one with a specific improvement. Saying "we could have done more repeats" is worth nothing on its own. Saying "only three repeats were carried out, so an anomalous result had a large effect on the mean, and running five repeats would reduce this" is worth the mark.

Structure. Marks for a report that has an informative title, a clear structure with the sections in a logical order, and references cited properly.

04The research stage

Your notes are the only thing you can take in, so they should be built for the write up, not for reading. Structure them as the report: aim, underlying biology, method, results table, published data, evaluation points. Include the exact numbers, the exact citations, and the specific vocabulary you intend to use.

05Common ways students lose marks

Writing an aim that is vague, so the conclusion cannot match it. Presenting raw data without units. Drawing a bar chart where a line graph was required or the reverse. Writing an evaluation that lists problems without linking them to reliability or validity. Running out of time and leaving the evaluation half finished, which is why you write the sections you are surest of first.

06A practical plan

Pick the topic three weeks before the write up. Do the experiment early enough to repeat it if it fails. Draft the full report at home as practice, get feedback, then rebuild your research notes around the gaps that draft exposed. Time yourself on the write up at least once.

An 18 out of 20 assignment plus a decent exam is an A. An 11 out of 20 assignment means you need an outstanding exam. The difference between those two is about three weeks of ordinary effort in the spring.