This "Science note" arose out of practical work involving the dilution of ethanoic acid, the measurement of the pH of the diluted solutions and calculation of the acid dissociation constant, K[subscript a], for each diluted solution. The students expected the calculated values of K[subscript a] to be constant but they found that the…

The physics curriculum is usually defined by content but this does not provide students with an authentic experience of the subject. An alternative is that physics is defined more as a way of thinking and this idea is explored in terms of the purposes of physics education, assessment and the relationship of the subject with other disciplines. A…

Electricity from osmotic pressure might seem a far-fetched idea but this article describes a prototype in Norway where the osmotic pressure generated between salt and fresh water drives a turbine. This idea was applied in a student investigation, where they were tasked with researching which alternative materials could be used for the…

There is growing interest in the use of low enthalpy geothermal (LEG) energy schemes, whereby heated water is extracted from sandstone aquifers for civic heating projects. While prevalent in countries with volcanic activity, a recently proposed scheme for Manchester offered the perfect opportunity to engage students in the viability of this form…

Global warming is a current environmental issue that has been linked to an increase in anthropogenic carbon dioxide in the atmosphere. To raise awareness of the problem, various simple experiments have been proposed to demonstrate the effect of carbon dioxide on the planet's temperature. This article describes a similar experiment, which…

From September 2015, schools in England will be teaching new A-level science specifications that have been developed by examination boards to encompass new higher levels of demand developed by the Department for Education. Integral to these new specifications is a radical change to the contribution of practical science to the A-level grade of the…

Science is at heart a practical subject, but the perception of what makes good teaching and learning through practical science is often misunderstood. Through working with teachers on professional development courses at the UK's National Science Learning Centre, and drawing on work carried out by other organisations, we present some thoughts…

In this new context concept approach, field research on the Trinidadian guppy is used as an appealing example of evolutionary change in populations. Pupils are asked to investigate the underlying mechanisms. In doing so, defects in their knowledge are revealed, in particular the role of meiosis in creating genetic variation. The reason for these…

The "Saggi di naturali esperienze" was published in 1667 by one of the earliest scientific societies, the Accademia del Cimento. The book was a triumph for the ruling Medici family of Florence, and the commitment of the Accademia to experimentation helped the "Saggi" become the "laboratory manual" of the 18th century.…

We often say that food and fuels "contain" energy, whereas energy is stored in the fuel-oxygen system generated during photosynthesis. This article suggests revised approaches to teaching that make a clear distinction between matter (food, fuel, oxygen) and energy. (Contains 1 table, 5 boxes, and 6 figures.)

When you dive underwater, you feel the pressure on your ears and, as you dive deeper, more pressure is felt. This article presents an activity that teachers might find useful for demonstrating the relationship between water depth and pressure. (Contains 5 figures and 1 table.)

Foams or bubble dispersions are common to milkshakes, bread, champagne froth, shaving mousse, shampoo, crude oil extraction systems, upholstery packing and bubble wrap, whereas the term droplet is often synonymous with either a small drop of water or a drop of oil--a type of coarse dispersion. The latter are seen in butter and milk, household…

African violet (genus "Saintpaulia") was identified as a particularly suitable genus for the study of specialised plant cells in the classroom using microscopes. The techniques described here involve simple preparation without staining. The cells and structures that can be investigated include: trichomes (hairs); stomata; guard cells and…

Open day activities rarely give applicants a real sense of the practical and intellectual work that goes on in university chemistry departments. We devised an experiment for year 13 (age 17-18) students based on the size-dependent colours of gold nanoparticles and linked this to current research in diagnostic medicine. The experience was designed…

In a relatively short space of time, classrooms have become full of computers, gadgets and electronic devices. Technology will only continue to become more sophisticated, more efficient and more abundant in schools. But how desirable is this technological revolution and to what extent should it develop? To measure the effectiveness and popularity…