Jump Sizer Open
menu
Skip Counting Tool
Skip Count by
Jump Sizer Closed
menu
Skip Counting Tool
Menu tools:
Icon/Image
Tooltip
Default jump
sizer
Action
The user can use this to set the size of the next jump they
place on the number line by dragging the right hand side of the
arrow forward and backward. The number line that the skip
counting sits on is scaled according to the scale on the number
line given and should snap to those increments.
As the jump is dragged to the right, the number line (below the
jump sizer only) should shrink (w/o changing scale) to allow
more increments on the line. (i.e.. if the diagram shown is
dragged to the right, 7/4 should be added then 2, then 9/4 etc)
When they let go, the jump sizer number line should shrink a
bit more to show at least one more step on the number line.
Skip Count by
Default jump
size
Point
Skip Jumper
Or
Jump
Hand
Dragging the end of the jump sizer arrow to the left of 0 would
similarly change orientation of the jump sizer arrow, and slide
the scale to become right-aligned and going in the negative
direction.
If the Default jump sizer is changed, then the number in this
box should change to match. Or the user can type a number in
this box and the sizer should scale to match. Note: If the
number that they type in doesn’t have the same scale (denom)
as the number line, then the jump sizer should not snap to the
scale spots (so in the above if they type in 1 1/8, then the jump
should land half way between 1 and 5/4 but the scale shouldn’t
change)
When this tool is selected, the user can place points on the
number line to either
a) Start a skip jumper (point drops onto the line and marks the
starting point for future jumps)
b) Split a jump: i.e. if a jump is 1 ¼ long starting at zero, then
placing a dot at 1 will allow them to pull the skip jump down
(with the hand tool) to create a jump from 0 to 1 and
another from 1 to 1 ¼.
c) Move the set of Jumps to a different starting point: If a
point is added after jumps are on the line that is outside of
the current set jumps, then the entire set of skip jumps will
shift over so that the initial jump starts there.
When this tool is selected the user can add jumps to the
number line by:
a) clicking (press and release) on a dot that’s already created,
then the current default jump size will appear. (note: if they
click on the number line and there is no dot or skips on the
line, then the default skip jump will appear at zero)
b) clicking on the end of a jump already created, then the
default jump will appear there (if there are jumps to the
right, then move them to the right to make room for the new
jump)
c) pressing on a point on the line, and dragging, and then
releasing: then a jump of size determined by how far they
dragged will appear – this should also snap to the scale
given.
d) If a point exists in the middle of an arc (eg. in above pic @
2) and the user clicks on it, then split the arc above it into 2
arcs (eg in above into 2/4 and ¾ arc), and squish the new
arc between those two (move the 2nd arc (3/4th), and all
arcs to the right of it, over to the right to allow the default
arc in) <see Figure 1 below>
This tool allows skips on the line to be adjusted.
Click on the arc part
 Click, drag up and release will poof the jump clicked on (i.e.
make it disappear) All jumps to the right of that jump should
slide backwards to line up on the number line (I think?)
 Click, drag right or left and then release will move an
selected jump along the number line (so this allows for
rearranging of jumps)
 Click and drag down to a point will split an arc (must have
points made by the point tool?) Click and release on an arc
will change the default jump sizer and the default jump size
<none>
Hide/show
jump sizer
to both match that of the arc click on.
Click on a point of intersection of 2 arcs and drag up will merge
the two arcs into one larger arc
Click & drag on the arrow head (the pointy part) then that will
change the length of the jump that is already on the line and
this will also snap (don’t forget to adjust the tool tip)
Clicking the up/down arrows on this works the same as the
other fraction ops tools. Some additional notes:
 If the scale changes the arcs should not snap to the new
scale.
 If the number line gets too long for the stage (number of
units) then the line should shrink to fit the stage (if it gets
hard to read the scale, show only some of the minor scale
labels, i.e. in above show only labels of 1, ½, 2, 3/2 etc with
unlabeled ticks in between for ¼, ¾, etc)
 Reset button resets everything (scale back to 1, length
back to 1, no jumps on the line)
Raises and lowers the box with the jump sizer and skip count
by tool in it.
Add tool tips to all jumps that have their size on them, so that no matter which tool is in use, hovering
over a jump will show the size of the jump.
When the tool is created by the programmer, they should specify where to put the tool box and the
number line… eventually it would be nice if this whole thing was also available in a ubPod.
*Design of skip jumpers is up for debate.. would like the arc/arrows to be more than just lines, but
need not be funky like above ones either – they would be hard to make dynamic – in the end, an
arrowed line might be the only thing that works and I’ll be fine with that!:)

All the jumps should always be in a continuous line (no spaces between jumps) – so as jumps are
moved around or removed, the jumps remaining will shift left to join the jumps that are there.
Options for use:
1. Place entire tool on the stage as part of the activity (so feedback can be given on the number
line, jumps and can use the toolbox/menu)
2. Place the menu part in a ub pod so it can be closed with the number line on the stage as part
of the activity. (so feedback can be given on the number line and the jumps)
3. Place the entire thing (including the number line) in a pod… for student use, but no
programmed feedback given on the line or jumps.
Figure 1
Dot is already on the line and the user clicks the dot after selecting the jump tool
The jump begins to split into 2 jumps to make room for the new one (this is the same as
when the arc is dragged down with the hand too to make 1 jump into 2)
/
Split completes (dot can disappear at this point, left there as a visual reference for you)
Default jump comes down and squishes itself between the 2 new arcs (need not be a
different colour, just different here so you can see how it works)
The jumps to the right of the dot get shifted right so that the default jump can fit in.