2.NBT.B.5 — Fluently Adding and Subtracting Within 100

Second grade is where two-digit arithmetic is expected to become quick and reliable rather than carefully constructed. The standard deliberately does not prescribe the standard algorithm — strategies based on place value count, and for many second graders they are faster. What it does require is fluency, which means the regrouping cases have to work too, not just the friendly ones.

The standard, word for word

Quoted verbatim from the Common Core State Standards for Mathematics. Nothing here is paraphrased.

2.NBT.B.5	Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.

In plain English: Add and subtract within 100 fluently, using place value and the relationship between addition and subtraction.

Free Grade 2 activities that practice 2.NBT.B.5

Each one runs in the browser with no account and nothing stored. Five questions apiece.

Addition within 100Grade 2 · 2.NBT.B.5 Subtraction within 100Grade 2 · 2.NBT.B.5

Or solve the whole free Grade 2 case →

What 2.NBT.B.5 looks like as a question

Real output from the activities above — not written for this page, drawn from the same pools a student gets. The numbers are rebuilt on every attempt.

🛰️ Addition within 100 — Plot the Course

62 + 17 = ?	79
37 + 42 = ?	79
80 + 17 = ?	97

🔐 Subtraction within 100 — Crack the Airlock

51 − 19 = ?	32
29 − 20 = ?	9
90 − 34 = ?	56

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