1 What’s Next?

Students are often given a number and asked to give the next number going forward or backwards.  I would say, “We’re counting by ones, I will give you a number, you give me the number that comes after it.”  Then I would give random two digit numbers (16, 77, 33, 80, etc.)  If the students are secure with that, then we would do the same activity but ask for the number that comes before it.  (Always include practice counting backwards in any practice you do!)

First Variation

After that, I will aim for specific numbers that I know will be a challenge.  Do the same activity above, but make sure all the numbers you give for going forward end in 9 and start throwing in three digit numbers too ( 49, 29, 89, 59, 109, 269, 599, etc.).  When you do this activity working backwards, use numbers that in in 0 (50, 20, 90, 100, 460, 180, 300, etc.)

What you’re looking for is whether or not the students can make the change into a new ten or hundred.  If they can’t, you’ll need to go to a visual and use paper and pencil or chalk and slate board.  Help them make a pattern out of it.  For example, write this at the top of the paper, 99, _______.  Then ask the students to tell you or write what comes next.  Underneath that, then write, 199, ______, and continue in the same fashion so the students can see a pattern develop.  Then do it going backwards.  Write at the top of a paper, 900, ________ ask the students what number comes before it.  If they don’t know the answers, just tell them at this point.  What you want them to see is the pattern.  After you have a whole row that looks like this:

899, 900

799, 800

699, 700

599, 600

499, 500

399, 400

299, 300

199, 200

99, 100

 

Extension

Use four digit numbers.  If the students are very secure in the above activity, give them numbers like the following:

What comes after each of these numbers?  1,049; 2,909; 5,999; etc.

What comes before each of these numbers?  1,000; 2,100; 5,010, 6,009; etc.