Measuring Weight
Lessons in this chapter
About Measuring Weight
Weigh it Out moves from 1st grade’s hefting objects by hand to grams and kilograms, which is where weight gets a number attached.
Measure Mass in Standard Units introduces grams and kilograms and the balance or scale that produces them. The useful anchors are everyday: a paperclip is about a gram, a bag of sugar is about a kilogram, and having those in mind is what stops a child writing an answer that is a thousand times out.
Solve Applied Problems on Comparison and Addition and Subtraction of Mass then uses the numbers. The arithmetic is 3-digit addition and subtraction, already covered, so the new work is entirely in reading the situation and keeping the units straight.
With two lessons this is a short chapter, and it is short because the measuring itself is simple once a scale is doing the work. The idea that mattered, that weight has to be felt rather than seen, was established in kindergarten and 1st grade.
Measure Mass in Standard Units and Solve Applied Problems on Comparison and Addition and Subtraction of Mass are the chapter's two lessons, and each opens as a worksheet in the page, marked as your child answers. The second is where the math problems live: comparing two masses, then adding and subtracting them. Both are free to practice online.
Frequently asked questions
Measuring mass in standard units, grams and kilograms, and then applied problems that compare, add and subtract masses. Two lessons is the whole chapter, because the reading of a scale is the only new skill and the arithmetic is already familiar. The Common Core puts mass in Measurement and Data, but not until 3rd grade (3.MD); at 2nd grade the measurement standards (2.MD) cover length, time, money and data.
Grams and kilograms, with 1000 grams in a kilogram.
In everyday use at this level they are treated as the same thing: how heavy something is. The distinction between them is a physics idea for much later.
A paperclip is roughly a gram, a bag of sugar is roughly a kilogram. Those two anchors catch most answers that are wildly out.
Because size and mass are not the same. A large empty box is lighter than a small full one, which is exactly why standard units and a scale are needed.
The 3-digit addition and subtraction from earlier in the year. Nothing new, which is why this chapter can be short.