A parent must know what level of math and any other subject, for that matter, that their child is performing at every school year. When children enter kindergarten and the school recommends that children know their ABC's and know how to count to twenty or whatever number, it is the parent's responsibility to make sure the child is prepared prior to enrolling in school.
Parents can assist with developing a lot of the fundamental skills needed for children to succeed in math when they attend school. Parents can do things that will support the schools and hopefully the schools will do the rest.
Some have a time limit to complete tasks, much like a game. If the math problems are not completed in time, a buzzer sounds indicating that they are out of time. This raises the competitive level from simply completing tasks to competing for how quickly they can do it, and do it correctly.
Children naturally love counting and doing puzzles, but for some reason, when you call it "math", all of the interest flies out the window! So how can you cater to this natural love of 'math' and keep it fun and interesting enough to keep children's interest?!