Estimating how many objects

Fun with counting, estimating, adding and subtracting and even a bit of subitising.

I set up this activity by putting different objects in three bowls and asking the kids to estimate how many of each they thought were there - just by looking. Then they counted. And then they worked out how far off their estimate was from the actual number in the bowl. We then had a discussion around comparing the estimate and the actual.

Sometimes we do this activity as part of lunch, so I use food based objects and they eat as they count. To keep track while eating, my eldest uses telemarks. We use peas, bocconcini, grapes, pasta, apples and crackers but you could use edamame, rice, chickpeas, corn, tomatoes, strawberries, cheese, bananas or any other type of food you would like to involve in this positive eating experience.

As I’ve mentioned many times in my posts, my youngest son is a very picky eater so I would normally struggle to get him to eat a range of healthy foods. However, I find when I present a variety of food in this manner he doesn’t protest one bit. Winning.

Last time we did this, my daughter made a really interesting observation and did a super job of communicating her findings to me. She noticed that when there are only a few objects in the bowl it was really easy to estimate correctly compared to when there were many objects in the bowl (we talked a bit about subitising here - the ability to look at a small number of objects and instantly recognise how many objects there are without needing to count). She also noticed that estimating the apples was easy because they were in groups and clearly defined slices but she struggled to estimate the curly pasta because “they were all joined together and look like one big piece. I couldn’t tell where each piece ended so it was really hard to guess how many”. 

I recommend when you try this to choose some objects with uniform shapes and others with random shapes. Also, try it with few objects and also with many.