Primary students (K-2): number recognition, counting, patterns
Intermediate students (3-5): patterns, multiplication, algebra, functions
This is a horizontal function table. A function table shows the relationship between the X and the Y numbers. For this table, 'X' is the Blue Windows and 'Y' is the Total Red Blocks. What's important in a function table is that the function (pattern/rule) must apply to all the numbers in the table. This function is represented by the equation: y = 2x + 2. Following this rule, the answer for 50 blue windows is 102 total red blocks.
In the middle school years, students will learn that the number associated with 'X', in our case '2', is called the coefficient of X. This coefficient appears in our table as the difference between the numbers in the 'Y' row. Students at the elementary level can easily see this difference and will often say the numbers are "counting by twos."
"Each red one is 2 times the blue number plus 2. 2x + 2 = y"
"Red = Blue x 2 + 2. Missing Reds = 14, 16, 18, 20, 102."
"It counts by 2's."
"2 reds and then blue window."