I have used those times tables in the past and they work great! The one thing we need to do when adapting the pages for our students is their grade and ability level. These pages were made for a student with multiple impairments in a self contained classroom. The teacher has a wonderful system of teaching these items to her students and I adapted the pages to be as close to what she uses so my student could benefit from the instruction as well.
For an example of what Richard is talking about http://www.rapidtables.com/math/number/mult-table/multiplication-table-p...
For numeracy there is a compact form of the 10x10 times table that could be a suitable addition as for your hi-vis calendars, or just for general use.
The table is a square grid 10x10 with a heading along the top (0 to 10) and a margin on the left (0 to 10) so that the top left square is the zero in both cases, or could be just "x" to show multiplication.
Each interior square is then the answer for the multiplication of the row and column. So the intersection of 2 along and 3 down is '6'.Similarly 3 along and 2 down is also '6'.
The learner can see that the whole grid is symmetric about the diagonal. To help this insight, the diagonal is highlighted (or framed) to show it is different.
Further insights are available, eg the numbers crossing the diagonal are one less: (x-1)(x+1)=x*x - 1.
The same structure can be used for addition, with the sum in each interior square and changing "x" for "+" in the top left square.
It's also very important to keep to 10x10 because it illustrates, like an abacus, that decimal numbers are simply the digits 0 to 9 with position values. This is the mental foundation for introducing binary and hexadecimal later in life.