If you went to school in the 40's and 50's, math lessons were not only boring, but often futile for the less-than gifted student. High school was worse because the math teachers were under the impression that, since they 'got' math quite easily, the students should as well. I had some gaud-awful math teachers and, for me, mathematics was an ugly exercise.
In grade school we copied and copied stuff from our workbooks and 'practiced' the rote lessons until our fingers blistered from holding the pencils too tightly. Then we went home and did the same nonsense there for another hour. Memorizing 'facts' was little more than drill and kill. The 'math' lessons were appropriately called arithmetic which might have been useful if we intended to grow up and become shop keepers. For most of us, it was pure boredom and it killed any desire to move on to higher level math.
Thankfully, times have changed for most kids in school today, because teachers, textbooks and curriculum have been updated and math class is truly math, not just arithmetic. I came across a lesson at this LINK that would have been useful to me in 3rd or 4th grade. Rather than rote memory and mounds of practice sheets, this lesson clearly demonstrates the intricacies of mathematics in a relational format that actually makes sense to the student.
Note the subtle algebraic equations that accompany the 'fact families.' Note also the diagrams which begin lessons in geometry. The total set of mathematical relationships are offered to the student in one sitting. Wow! If only I had been born 60 years later, I might have become an aeronautical engineer!