Method 1:  Constant Key

Press the 2nd CONST key (Constant Key) to set up a constant operation. 

Place the MODE on mansimp.  This means you will manually simplify the fractions. 

Set the C1 = +1/8.  Remember to use the b/c key to enter the fraction.  Leave highlighting on Single.

Return to the homescreen by pressing 2nd QUIT (MODE).  Clear the homescreen by pressing CLEAR one or two times.  The begin skip counting by  eighths press 0 CONST.

By pressing the CONST key again and again you will see the calculator skip counting by eighths. 

On the left is an addition problem.  For example we started with 0 and added 1/8.  The calculator show that we added one 1/8 and the result was 1/8.

The second line shows we started with 1/8 and added a second 1/8 and the result was 2/8.  The calculator indicates that this fraction can be simplified. 

If we don't simplify we can continue skip counting by eighths. 

The third line shows we started with 2/8 and added a third 1/8 and the result was 3/8.

Students could be asked to use the constant key to create several skip counting patterns. 

Students can re-enter fractions to simplify them.

Be sure the NumLine APP is loaded in the TI73

You have set up the window to skip count by 4. Press GRAPH and then use the cursor arrows to move along the line. Complete this list below to count by 4's. The window will adjust to keep counting.

Notice that if fractions can be simplified  an arrow is placed next to the fraction.  At this point you can press SIMP and the fraction will be simplified. 

Then if you continue to move along the number line you will see the next fraction value as we count by 1/8. 

Students will start at 0 and count by fractional units by setting up the window as indicated.