This is a good introduction for kids who have never used a scale before. By building the scale themselves, kids gather an understanding of the mechanics of the scale. They'll also be able to observe how objects that are the same size may not be the same weight.
What this activity will develop:
What you'll need:
• Oats box
• Scissors or knife
• Cup hook
• Rubber band
• Four paper clips
• Plastic lid
Cut a window from one side of the oats box.
Screw the cup hook into the top of the oats box. Attach the rubber band to the hook.
Open each paper clip to form an S shape. Hook the end of one paper clip over the rubber band.
Cut three evenly spaced holes at the edge of the plastic lid. Hook a paper clip through each hole.
Tie the three paper-clip ends together with string. Then tie the other end of the string to the fourth paper clip.
What to do:
First, find a food item that has the weight marked on the package. Weigh it on the spring scale and mark the oats box to show the level of the lid for that weight. To mark more weight levels on the scale, find objects that weigh one-half and one-fourth as much as the first object and mark the oats box to show the level of the lid at these weights. Now you can weigh other items and use the markings to determine their weight.
Gather several items that seem to be the same weight as the first. Place each on the lid, and see how it compares to the known weight. Were certain items heavier or lighter than you predicted? Talk about how size and shape can alter your perception of an item's weight.
Challenge a friend to find objects that are similar in weight to those marked.