If you are trying to learn to play the piano and you never bother to master reading the notes on the staff, how well do you think you could play? You’d have to figure out each individual note of the staff by reading Every Good Boy Does Fine or Good Boys Do Fine Always each and every time! That would get frustrating, right? In order to learn to play the piano, you need to commit the notes to long-term memory so that you can find them quickly. You can then go on to play pieces that are more challenging than ‘Twinkle Twinkle Little Star’.
Learning multiplication facts is just as important to math as learning notes is to music or to learning letter sounds when reading. Committing the facts to long-term memory helps students quickly and easily access the facts so that working with math concepts becomes fluent. Finding Area and Volume in geometry is dependent on knowing multiplication facts. Using Algebraic formulas is dependent on knowing multiplication facts.
What to do? Practice, practice, practice! Jump on the trampoline and shout out facts (research says that physical activity + verbal practice = memory storage); use games online; bust out the flashcards; sing songs and listen to the facts set to music; devote time every day (just 5 minutes makes a huge impact) to learning those facts!