A boring, but effective way to get up to speed is the Xtra Math iPad app. DD used it in 2nd grade when "speed tests" at school started with her higher math group. DD was pretty stressed in 2nd because she realized she wasn't always the fastest (which was GOOD for her!). This program really helped her automatically learn and recall the facts. In 3rd grade, the school started assigning it as homework for all of the 3rd graders - it DID build automaticity in addition, subtraction, and multiplication (don't ask me, but we didn't see division???).
DS6 also used it a bit last year when the pace of K was too slow. Since I know he has "learning facts quickly" in his "math future" at school, we found it to be a good challenge for him.
Added bonus - my kids love using the iPad.
