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An online lesson can centre on one visible piece of work: a diagram the learner annotates, a calculation they explain aloud or a graph they interpret. These constructed teaching examples show the reasoning a learner could practise.

GCSE: explain a change in potato mass

In an illustrative osmosis investigation, a potato cylinder has an initial mass of 2.00 g and a final mass of 2.20 g after being left in a sugar solution more dilute than the contents of its cells and gently blotted dry. The gain is 0.20 g. Percentage change uses the starting mass: (0.20 ÷ 2.00) × 100 = +10%. Writing “0.20%” confuses the change in grams with a percentage.

“The potato got heavier” describes the result but leaves the Biology unexplained. A clearer response is: “The potato gained 10% in mass because water moved into its cells by osmosis, through partially permeable membranes, from the more dilute solution outside.” This connects the calculation to the direction of water movement.

The learner could mark that direction on a cell diagram, then try a second constructed result: 2.00 g to 1.80 g. That is a −10% change, consistent with net water movement out of the cells into a more concentrated solution. When comparing solutions, keep the potato-cylinder dimensions, time, temperature and blotting method consistent. AQA GCSE Biology and Combined Science Trilogy both include plant-tissue osmosis and percentage mass change.

A-level: explain why an enzyme-rate graph levels off

The substrate is the substance an enzyme acts on. Consider initial reaction rate plotted against substrate concentration, with enzyme concentration, temperature and pH held constant. The curve rises, then approaches a plateau. A learner might say the enzyme has denatured, but the graph does not show a temperature increase or other evidence of denaturation.

At high substrate concentration, enzyme active sites are occupied much of the time. Adding more substrate has little further effect because the amount of enzyme limits the rate. A stronger explanation links the plateau to active-site occupancy and enzyme concentration. The follow-up is to predict what adding more enzyme would do when substrate is abundant: it provides more active sites, allowing a higher rate. AQA A-level Biology includes the effects of substrate and enzyme concentration; this task develops a molecular explanation beyond simply describing the curve.

Send the course title, awarding body, specification code and exam year when you have them. The examples here draw on named AQA and Cambridge courses; requirements for other boards and UK nations need to be checked against the learner’s own specification.

Screen-shared results can support work on variables, calculations, graph choices and conclusions. For the potato example, ask why equal-sized cylinders and consistent blotting matter: changes in preparation could affect the comparison between solutions. The learner can critique a method and interpret data online, while handling apparatus needs an appropriate practical setting.

For AQA GCSE Biology, schools and colleges must provide opportunities to undertake the required practical activities even though practical understanding is assessed in written questions. For AQA A-level Biology 7402, the practical endorsement is reported separately from the grade determined by the written papers and involves teacher observation of practical competence. Online question practice does not fulfil those arrangements.

Cambridge IGCSE 0610 Alternative to Practical is a written paper assessing experimental skills, not a reason to skip practical learning. If the learner is home educated or entering privately, confirm practical preparation and assessment arrangements with the exam centre before relying on online tuition alone.

Each tutor sets the hourly rate shown on their profile. Latimer invoices standard lessons after they take place on a pay-as-you-go basis, without requiring a long-term package. The matching request and introductory meeting are free.

Before agreeing lessons, confirm the duration, frequency and any cancellation arrangements with the tutor. If you expect marked practice between sessions, ask what is included. Assess value against the learner’s work: are they now choosing the right calculation, interpreting an unfamiliar graph or explaining a process with fewer prompts?