GAMES LEADING TO THE UNDERSTANDING OF CAPACITY MEASUREMENT

Arbitrary units of capacity

By playing to fill or empty a large container with the help of one or more small containers, it is how the child gains his first experience of volume or capacity. The best way to do this at school could be using dry sand instead of liquids, taking a cup as a small container, and a basin or bowl as a large container. For starters, there is no need to count or record how many cups have been filled. When the cup is full, it empties and starts again. Then the game can be varied by taking the same large container, but changing the cup for a smaller or larger one.

When children have become accustomed to these games and are able to count, they can be encouraged to pre-appreciate the amount needed to fill the large container, and then the number of cups they need.

Arbitrary unit series

It is necessary to have a series of containers of different capacities, but in the same way, in order to facilitate understanding. It would be desirable, initially, that containers with a fairly wide neck, and at the same time resistant, be available. type of the carafes. But what matters most is that between their different capacities there is a simple and interesting relationship.

As content, water can be used, but it can also be made with fine sand, rice, or any other "fluid" material. A funnel must be prepared for each group, and a coloured adhesive tape will be used to indicate the level to which each bottle must be filled.

Children can be asked to perform certain tasks, designed in ways that make it easier for them to understand the relationships between the various "units." They can be asked, for example, how many times can the contents of bottle # 1 be put in bottle # 6, or conversely, how many bottles # 1 do we need to empty bottle # 6 into them. redo the same exercises with jars of other calibers. Thus it is understood that a large number of games can be played with flasks of different sizes, which at the moment constitute our arbitrary units.

Arbitrary units of the same capacity but in different ways

These games are played with the same accessories, but adding other "units" of the same capacity, and in different ways. What matters is that children come to understand that the same amount of water or sand can be contained in containers of different shapes that have the same volume as the jars previously used, and to which they are listed in the same way, consequently.

Children begin by discovering which containers have the same capacity, even if their shape is different. For example, they will be made to look for the containers that correspond to bottle no. 2, making them fill this bottle with water and then empty it into other containers, until they are correct. In all cases, they must carry out the opposite test, putting the contents of the discovered container back into the original bottle. Since each numbered bottle must, in principle, have several equivalents, the possible games to be performed are numerous.

When the children have become familiar with these exercises, move on to the appreciation exercises. It is asked, for example, how many casseroles of nº 9 can be filled with two casseroles of n.0 4, etc. After assessment, the check is performed by effectively filling or emptying the containers.

Presentation of the legal units

As with length measurements, children will agree that if they have to talk about what they have done and the results obtained with someone who has not attended the operation, they should resort to the use of units known to all. Therefore, all containers are removed, except those that contain exactly one liter, half a liter or a quarter of a liter, and their designation by numbers is suppressed, henceforth giving them their official name. Children go to work, fill them up, empty each other, discovering the relationships that exist between them.