A worksheet is a good way to give instructions of how to carry out practical work safely and effectively. The students can refer to it whenever they are unsure of what to do next and they do not have to waste time copying out the method into their workbook – they can focus on the results and what they mean. However, one of the disadvantages of using worksheets containing detailed instructions is that students can end up following them passively, like a cookery recipe.
In view of this, I have started to develop worksheets for practicals that make extensive use of diagrams or photographs (images can be snipped from instructional videos on YouTube) and the minimum use of words. Furthermore, I include questions about what the students are doing and why they are doing it as discussion points at each stage of the process. Below is an example of one such worksheet that I made for an investigation of chlorophyll using paper chromatography.
I have recently discovered this wonderful app for making stop motion animated movies on the iPad. It is free to download from the App Store but includes a number of in-app purchases such as sound effects and movie themes which you may wish to invest in. Students can simply draw a sequence of images on paper to photograph or build models using plasticine, Lego or pipe cleaners etc. Most recently, my AS students (who are currently studying a unit on immunity) animated clonal selection and expansion in B-lymphocytes (below), phagocytosis and the action of antibodies.
By the end of Key Stage 3 pupils are expected to be able to describe the structure of an atom, relate atomic structure to information given for each element in the Periodic Table and show the arrangement of electrons in shells around the nucleus. It is vitally important that pupils develop a secure knowledge of these fundamental concepts in chemistry since a superficial understanding can result in misconceptions and pose significant difficulties in understanding higher-order content such as ionic and covalent bonding at GCSE and beyond.
Take your time, break down the topic into bitesize chunks and use plenty of diagnostics such as hingepoint questioning to gauge the level of understanding of the whole class before moving forward together. In addition to the following activities, provide pupils with plenty of practice in relating atomic number and mass number to the number of protons, neutrons and electrons in a neutral atom, and drawing electron shells.
Hula hoop competition
Explain that all atoms consist of electrons orbiting a tiny nucleus then have a hula hoop competition! Who can keep their electrons orbiting for the longest?
Provide pupils with laminated electron shells, an element symbol, a particle key and coloured plasticine. Ask them to build an atom of the element they have been given before taking a photograph and sharing it with the class via Padlet.
Build giant models of atoms using foam balls, craft straws, pipe cleaners and wire etc. These make excellent mobiles which can be hung in order of atomic number along the length of the science corridor.
Alternatively, bake (or buy) cookies and decorate them with proton and neutron M&Ms and silver ball electrons.
Facebook profiles or cubes
Facebook profiles or these simple cubes can be used to present information on all manner of things in science (e.g. famous scientists, types of nuclear radiation, specialised cells). Ask the pupils to investigate the element for which they built their plasticine atom and then complete a Facebook profile or cube for it. Who discovered it? When was it discovered? Is it a metal, non-metal or semi-metal? What are its properties?
The half-life of a radioactive substance is the time it takes for the number of parent nuclei in a sample to halve, or for the count rate from the original substance to fall to half its initial level. Half-life is random and it is impossible to know which individual parent nucleus will be the next to decay. LEGO and M&Ms can be used to model this random decay while also negating the need for students to handle radioactive materials.
Students start with 100 M&Ms (other sweets can be used so long as there are two distinct sides e.g. Skittles) and tip them into a tray. Record the number of M&Ms which have landed face-up (these represent parent nuclei which have decayed). Remove these ‘decayed’ nuclei and tip the remaining M&Ms into a second tray. Once again count the ones that have ‘decayed’ and repeat until all of the M&Ms have gone. Use the data to plot a half-life curve.
Students throw 60 2×2 LEGO bricks into a tray and remove all of the bricks that land studs-up (these represent parent nuclei which have decayed). Stack these bricks together to show the activity i.e. the number of decays per throw. Throw the remaining LEGO bricks and again remove those that have ‘decayed.’ Stack these into a second column and place this next to the first to quite literally build an activity vs. throws bar chart. Repeat until all of the LEGO bricks have gone.
Canva is a free online graphic design tool which can be used to make beautiful posters, infographics, presentations and many other things. It is extremely simple to use and features a vast library of templates, fonts and photographs to choose from.
My AS level biology students have recently used Canva to create eyecatching infographics summarising the structure and properties of biological molecules. I think they look great!