Before I was a mom, I was a second grade teacher. My advice is keep it fun and keep it hands on! Also, try to incorporate it into every day life. For example, if she has some grapes for lunch count the grapes. Let's say there are ten grapes. On her plate have her put the grapes into two piles. Then ask her what addition sentence she sees. If she has two groups of five, say "I see 5+5=10." Play around for awhile and see how many different addition sentences she can make.
Say you are giving her a snack of animal crackers. Show her that in one hand you have 4 and in the other you have 3, ask her how many animal crackers she is getting altogether. Kids especially like this one with Skittles or M&M's.
There are countless ways to explore addition and subtraction with food, but you can also involve math when playing. Say she likes Barbie dolls. Put two Barbie dolls in the house and three in the car, say I see "2 + 3 Barbie dolls, how many barbie dolls do we have altogether."
Another time to work in math is when she is doing chores. Let's say she is setting the table and you have three people in your family. Hand her three bowls and three plates, then say " I see 3 plates and 3 bowls, how many dishes altoghether, 3+3=" Or if she is helping to put away clean clothes, hand her 2 t-shirts and 2 pairs of shorts, "Say I see 2 shirts and 2 shorts, I see 2+2, what does that equal?"
The point is it is going to take more work and more creativity than handing her a workbook page, but if you get creative you could have your daughter doing math all day long in short little "mini-lessons," and she won't even know it! Let her experience the numbers and the addition and subtraction "hands-on", so she can touch and see the math. Another piece of advice focus on addition first!
Best of Luck!
