1.NBT.C.5 — Free Activities & Worksheets

Free Common Core 1.NBT.C.5 activities and worksheets for Grade 1, aligned to the Number & Operations in Base Ten strand. Browser-playable interactive exercises plus printable PDFs, available in all 11 supported languages — no signup, no paywall.

Grade 1·Number & Operations in Base Ten·1.NBT.C.5

Interactive activities

Grade 1·1.NBT.C.5

Ten More, Ten Less — Mental Math With Two-Digit Numbers

Find 10 more or 10 less than a two-digit number — all in your head. Look at the tens: only the tens digit changes, so there is no counting. Tap the number you think is right, and take all the time you need. A calm way to build place-value sense and mental math, aligned to Common Core 1.NBT.C.5 — mentally finding 10 more or 10 less than a two-digit number without having to count.

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Frequently asked questions

What is covered under 1.NBT.C.5?
1.NBT.C.5 sits in the Number & Operations in Base Ten strand for Grade 1. This page gathers the free interactive activities and worksheets aligned to it.
Are these 1.NBT.C.5 resources free?
Yes. Every activity and worksheet aligned to 1.NBT.C.5 is free to use online and to print — no signup and no paywall.
Who are these 1.NBT.C.5 activities for?
They are built for Grade 1 teachers and learners following the Common Core Number & Operations in Base Ten progression, and work for class, small-group, or home practice.