1.NBT.C: Use place value understanding and properties of operations to add and subtract.
![](http://c.gigcount.com/wildfire/IMP/CXNID=2000002.0NXC/bT*xJmx*PTEzNjIyNzY4MjMxNTcmcHQ9MTM2MjI3NjgyNTYyMiZwPTk3NTA3MiZkPTAwMCUyMC*lMjBWb2tpJTIwV2lkZ2V*Jmc9/MSZvPWJkNDMxNzc4ZDEyYzQ4ZDg5ZWZhYjNmOWE5NDMwZjE4Jm9mPTA=.gif)
First graders need to be able to add two-digit numbers up to 100. By the end of first grade, students should be able to add a two-digit number to a one-digit number, and they should also be able to add a two-digit number and some tens. Students need to be able to find ten more or ten less than a number, without having to count. Finally, students should be able to subtract by some tens, and explain their answers. Click on the links below to practice using place value to add and subtract!
For Students!
How do you know if you need to regroup? Check out the chart above to help you figure it out! If you have more than ten ones, you definitely need to regroup! Just trade in ten of your ones for a "long" ten, and you have successfully regrouped!
Check out this chart to help you regroup when adding two digit numbers! It shows you how to solve the first one digit problem before moving on to the second two digit problem!
Click here to learn about addition with regrouping. Watch this video, and practice this at home with your parents!
Click here to practice adding two-digit and one-digit numbers. This is a great printable activity!
For Teachers!
Click here to access great games to practice regrouping with your scholars. The best part about this article is that it allows for differentiating the games to a lower level for those children who are not quite ready to complete the task with three digit numbers at this time! These games will make great center activities once taught to your students.