Task 1

Materials and tools for a working group:

seeds, soil, water, black cloth, 3dcl plastic cups, tray, plastic spoons, sticky paper to mark the cups (or a black, non-washable marker to mark the variable under study on the plastic cups)

The teacher can start an activity by explanation that he wanted to plant tomatoes on the balcony at home. But when he bought seeds in the store to plant them at home, he didn‘t know what he needed and how to proceed. He then discusses what pupils would advise – the pupils suggest the procedure, as well as the necessary tools and the material they need. The teacher also asks them: Does the seed need soil to germinate? Can we put it in another material? What e.g. into the sand? Or cotton wool? Do you think the seeds will need light? Or does it germinate in dark? In this way, teacher tries to identify pupils‘ ideas of seed germination. At the same time, he does not evaluate or comment on ideas.

Once the predictions have been made, the teacher asks the pupils to think about how they could verify their predictions. If they want to find out what the seed needs to germinate, they need to change only one variable (e.g. presence of water, while other conditions such as light and temperature are the same – task 1b). If they were to change several variables at once, they would not be able to evaluate at the end what caused the seed (not) to germinate.

Therefore, it is necessary to prepare several cups to plant the seeds and mark the investigated variable on it. As pupils do not work on the result immediately in lessons, it is recommended to label the containers according to the examined variable so that they do not mix over time.

Similarly, when checking the predictions, the teacher makes sure that the pupils change only one variable at a time, while the other conditions do not change. We recommend planting more than one seed at a time (the seed may be old or damaged). After verifying, pupils evaluate their findings and draw conclusions. Pupils will find that the seed needs water, heat and air to germinate (light is not needed). However, the study of variable air is complicated because it is impossible to ensure air-free conditions (even if we place an overflow into a bag or a sealable container, for example, air will still be present). For this reason, the teacher can supplement this information and discuss it with the pupils.

The teacher discuss with pupils know quality of water they will use: hot, room temperature, iced, salty, sweet, mixed with vinegar, etc. Pupils can also propose change of the substrate in which the seed is planted – sand, gravel, stones, cotton wool. Of course, other conditions important for seed germination should be ensured. E.g. if we change the substrate, we regularly water the seed and keep it at a temperature at which it germinated in the first task.