# 3.NBT.1. Use place value understanding to round whole numbers to the nearest 10 or 100.

 Rounding - Crystal Crash Throw your pickaxe at the correct crystal. This game has the following levels (taken from the new maths curricululum): 1. Round numbers up to 100 to the nearest 10 (Y2) 2. Round numbers up to 1000 to the nearest 10 (Y3) 3. Round numbers up to 10,000 to the nearest 10, 100 or 1000 (Y4) 4. Round decimals with one decimal place to the nearest whole number (Y4) 5. Round decimals with two decimal places to the nearest whole number and to one decimal place (Y5) 6.Round decimals with up to three decimal places to the nearest whole, one decimal place or two decimal places (Y6) This game, together with all the other crystal crash games,  is available as a single iPad or Android app. Rounding Answers Use the calculator to answer a question and then round your answer to the nearest 10, 100, whole number or to 1, 2 or 3 decimal places. The correct answer is then shown on a number line. Play against the clock to see how many points you can score. Rounding Round 3-digit or 4-digit numbers to the nearest 10 or 100. Round decimals to the nearest whole number, or to 1 decimal place. Placing Calculations on a Number Line Place the answer to calculations on a number line. An enormous array of choice. Addition, subtraction, multiplication and division. Ranging from adding numbers to 10 to multiplying 4 digit numbers. Great for combining teaching calculations and approximations with developing an understanding of place value. For more resources involving partitioning and place value click here. For more addition and subtraction resources click here. For more multiplication and division resources click here.