Welcome back to school! I don’t know what the weather is like where you are (well unless you’re where I am!), but here it has hardly gotten out of the teens and my bones are chilled! It was nice to be able to be warm and cozy in Rm. 202 with my first grade buddies this week! Here’s what we studied:
Again, true story from my life used for our warm-ups. It really makes them interested in solving the problem when they care about the context!
This week we’ve been continuing to work on knowing if we should add or subtract. When we discuss the problems, the question I ask them is not “What answer did you get?” but instead they turn to their partner to tell them what operation they used how they knew what to do. I am listening for explanations related to the context and what is actually happening, rather than specific clue words. Just knowing clue words (like “left,” “in all,” or “how much more”) doesn’t always work; depending on how they are used in a problem, they can sometimes mean addition or subtraction. Or, you can add TO subtract (as in the strategy of counting up), so it becomes even more confusing.
This problem is an addition problem, but also gets kiddos thinking about multiplication without really knowing it. They have to really be thinking about the situation–I bought 2 bundles that each cost $20–or they will use the 2 and 20 and just add or subtract them. It was great to see how many kiddos understood the way the problem worked.
The focus with the numbers in this problem was to help mathematicians use known combinations to efficiently figure out unknowns. Ideally they would see make 5s to make 10 or see a 6 and a 4 to also equal 10. This idea of grouping connects to our future (well, really continuing) study of place value and addition numbers within 100.