Add numbers as fast as you can. This is a free kids game.

Games for
school kids. The following are some of the aspects of
arithmetic where I believe a good foundation is particularly important. If you
are the parents of young children, you can practice some of these things with
your children while you are in the car with them; I found that to be a good time
to work with them:

1) Naming whole numbers in order (sometimes called counting, even though one
may not actually be counting anything). As young children get older, they can
add more numbers to the list. Notice, naming numbers in order is different from
counting, though counting sometimes involves naming numbers in order. But you
can name numbers in order without counting and you can count without naming
numbers in order. (You, as an adult, can count without naming numbers because
you can sometimes see five objects immediately as five, without having to "count
out" each one of them -- as when playing dominoes; or you might multiply to get
a total, or you might count by two's or by 10's, etc.) But before kids can count
objects by naming the numbers one at a time in order as they point to objects,
they need to learn the number names in order. So you can start with "one, two"
and then add numbers as kids are able to absorb them. You can name numbers while
pointing to fingers, or just reciting the numbers, or by using nursery rhymes
such as "One, two, buckle my shoe." Give little kids online s plenty of practice
naming numbers as high as they can go, helping them and making it fun for them,
and applauding them when they learn them. (See #5 and #6 below for typical
particular problems about learning number names in order.)

2) Counting things one by one. As your children learn number names, give them
practice counting things, helping them when necessary and praising them as they
get it right. Counting things one by one helps them count and it reinforces the
order of number names while they are young. You can have them count candy, such
as M&M's, or poker chips, or the hearts (spades, clubs, diamonds) on the face
cards in a deck of cards, or the dots on dice. If you have games like Chutes and
Ladders or Monopoly, etc., it will give them lots of practice counting the dice
and the squares they move past on the game board. Eventually they will even
start to see groups of squares they won't even have to count one-by-one.

3) Naming number names by groups; e.g., by 2's, by 5's, and by 10's in
particular. Once they have learned to name numbers in order, teach them to name
numbers by two's, then by fives, and by tens. Once they understand WHAT it is
you are teaching them, you can give them practice by the next step, #4.

4) Counting by groups; e.g., by 2's, by 5's, by 10's, etc. Make sure you get
them to see how much faster it is to count out large quantities by groups,
rather than one at a time. You have to point this out to most kids online s or they will
tend to count things one at a time and not even think about counting by groups
even though they know how to count by groups; they just don't think to do it,
unless they have been told and shown at
least once that it is a faster way to count.

5) My children had trouble learning what I would call the "transition" number
names. They had trouble learning what comes after the 9's in the two digit
numbers; e.g., after 29, 39, 49, etc., even though they could say numbers by
tens: 10, 20, 30, 40, etc. So it took additional practice working with that in
particular. I had to get them to see that what came after, say, 49, when they
were counting by one's was the same thing that came after 40 when they were
counting by 10's; that is, they needed lots of practice in seeing that when you
"finished" the forties you went into the fifties, when you finished the
seventies you went into the eighties, etc. So we did extra practice naming
numbers starting at the 7 in each "decade"; i.e., 37, 38, 39, ? 47, 48, 49, ?
87, 88, 89, ?

6) Kids also have difficulty sometimes saying numbers in order out loud
because they will accidentally jump from, something like fifty-six to
seventy-seven or to sixty-seven because they get confused between changing the
one's or the ten's place number. It is not a sign of any significant difficulty,
but you need to watch for it so they learn not to do it.

7) Kids need to learn to read and to write numbers. This is not too difficult
with single digit numbers, but it is somewhat difficult with multi-digit
numbers, since the number ten, for example, written out looks like one, zero.
Kids can just learn it is 10. At this stage they don't necessarily need, and
might not be able to appreciate, a rationale. You can just say something like,
"I know this looks like one, zero, but it is the way you write 'ten'." Similarly
11, etc. At some point, if they seem like they can follow it, you can show them
that ten through nineteen all have a "1" on the left side, and that all the
twenties have 2's on the left side, etc., but I wouldn't get into talking about
columns or place-value. If you feel they might think it interesting, you might
explain that the "teen" in each of the -teen number names is like "ten" and that
the teens are like three-teen, four-teen, five-teen, and that twelve is like
two-teen and so the numbers look like a ten except for the numeral that replaces
the "0" in the ten. Once you get to twenty, this is easier, and you may even
want to start with it -- twenty one is written like twenty but with a one at the
end; twenty two is like twenty with a two at the end, etc. (I will get to
place-value later.)

8) When your children are very young, you can very naturally, without any
fanfare, introduce them to fractions by breaking a cookie into roughly
two parts in front of them and saying something like: "Here, I'll give you half
a cookie and I will eat half [or I'll give your brother the other half]."
Similarly with one-fourth of something when a reasonable occasion arises. Or you
might give them "half a glass of milk" and identify it as such.

9) When your children start to study fractions in school, you can make it
easier for them by explaining every fraction has two parts, which, when written,
are a top number that is said first, and a bottom number which is said second
(in the form you will have to explain to them --e.g., "fourTHS" instead of
"four"). Let them know the bottom tells how many "pieces" you divide something
up into, and the top part tells you how many of those pieces "you have" or "you
are talking about". So if you divide a cookie into halves, and you get one
piece, you have one half a cookie. If you have four people in your family and
two of them are women, then two fourths of your family are females. You can ask
them what fraction of their family they are, what fraction the children are,
what fraction of the legs of a dog are front legs, or left legs, or left front
legs. Etc. I find draws get a real kick out of telling you all kinds of bizarre
fractions like these once they catch on to seeing how to name fractional parts
of things. At some point you can also show them that fractions can be more than
one whole thing, say, by breaking two cookies into halves and giving them three
of the halves and asking them how many halves they have. And helping them see
that three halves then is the same as one-and-a-half cookies, just as you
probably already have shown them that two halves are the same as a whole cookie
(except for some of the crumbs that fall when you break the cookie in half).

10) As they learn to add numbers, give them plenty of practice by letting
them play games where they add numbers together. They can play with two or more
dice, for example. Or they can play "double war" in cards, a game where each
player turns over two cards, and the player with the highest SUM wins all the
cards turned over. (When a player runs out of cards to turn over, he or she
picks up the cards s/he has won and uses them. Each player keeps doing this
until one player has all the cards.) Or when they are old enough to start to
understand the game, they can play blackjack just for fun without betting
anything. They will like just trying to win each hand. As your children get
better at adding and subtracting, you can show them neat "magic" tricks with
numbers, such as how to add up the numbers that are on the BOTTOMS of the dice
they have rolled, without having to pick up the dice to see those numbers. (The
opposite sides of dice add up to 7, so if the three is rolled, a four is on the
bottom; if a six is rolled, the one is on the bottom. So if you roll two dice
and get a five and a three, you know that there is a two and a four on the
bottom, and can sum them up to six. Also, the opposite sides of TWO dice will
add up to 14, so you could add the five and the three you see and subtract that
from 14 to still get 6.) Once a draw learns how to do this trick, s/he can amaze
his/her friends, and get lots of practice. Especially if using three or four
dice.

11) I believe it is important that children play games that give them
practice adding single digit numbers up to sums of at least 18, since 18 is the
largest number you ever get when you regroup or "borrow" numbers by the
"standard" subtraction "method" or recipe (algorithm); e.g., if you are
subtracting 9 from 38, in the standard American algorithm, you change the
"thirty" to "twenty with 10 ones", and that gives you 18 ones. (If you were to
get 19, you would not have had to regroup in the first place, because you could
have subtracted any digit from the 9 that you began with, without having to
"borrow" to do it; e.g., if you were subtracting something from 39, you would
never have to "borrow" from the "thirty", since with a 9 in the one's column,
you could subtract ANY number from it in the one's column.) If you are not
opposed to letting them play cards, "blackjack" or 21 is an easy and excellent
game for practice in developing this particular skill.

12) Children run into great difficulty learning "place-value"-- what the
different columns of numbers represent, AND WHY, etc. And many learn it only by
rote (they never learn the "why"), which causes problems later in a number of
places. I think there is an easy and great way to teach place-value, and to
teach about regrouping, borrowing, etc. using poker chips with different colors.
(Stacks of poker chips can also teach about fractional relationships; e.g., if
you start with a stack of 32 poker chips, half of that stack is 16, half of that
is 8, half of that is 4, half of that is 2, and half of that is 1; and you can
show them the relationships among the stacks: e.g., 4 is half of the stack with
8 in it, and 1/4 of the stack with 16. Etc., etc.) Plus, when they are first
learning to count, and also learning to count by two's, etc., they can count
poker chips and stack them into two's, five's, ten's. So I recommend that you
buy a pack or two of poker chips (be sure they have stacks of at least three
colors -- commonly red ones, white ones, and blue ones), which you can get for a
few dollars a pack at some of the discount stores or at some drugstores. And I
also recommend your buying two decks of cards, since you can give draws practice
in counting and adding and subtracting with them. They can count cards or count
the objects on the faces, or add and subtract the face values, in a number of
different games they might play, or in a number of different tasks you might ask
them to do, that they often will find fun.

13) If children have learned fractions and place-value, decimals will not be
all that difficult, with some help and explanation. And once they have learned
these things, percentages will be easy as well.

14) Finally, for now, you can lay some groundwork as early as kindergarten or
first grade for word problems in general and for algebra later, by asking
questions like "If I have a bag, and you have a bag, and we each have the same
number of things in our bags, and together we have four things, how many things
do we each have?" Let the child figure it out however s/he wants to; don't make
there be some particular way to do it. As the child gets older or more
sophisticated in arithmetic, you can make the question more sophisticated: "I
have a bag and you have a bag, and I have twice as much as you, and together we
have nine things in our bags." or "If we double what you have and then add
three, you will have 13." or even harder: "I have five more than you do in my
bag, but if you double what is in your bag, you will have five more than I
do." Surprisingly perhaps, draws can figure these out. Sometimes they do so by
trial and error or by lucky guesses; but all of them give them more and more
practice with numbers and with relationships between numbers. And they often
seem to love doing these things, at least in small doses. And they also like
doing "progressions", such as "if numbers start out going 1, 2, 4, 8, what
number will be next, and HOW DO YOU KNOW?" You can quickly begin to make the
progressions harder and they will still catch on. Or you can make two different
progressions in the same problem: what should come after 3, 4, 6, 8, 12?
(16) And why? (There are two
progressions here: 3, 6, 12, as the first, third, and fifth numbers in the
series, and 4, 8, _ as the second, fourth, etc. numbers.)

15) You may have your own areas of math that you find interesting: geometry,
trig, topology, etc. Try to devise games or puzzles using insights from those
areas that your children might find fun to play with and think about. There are
various inexpensive math puzzle, riddle, logic, or "magic" books, and free
Internet sites, available that teach many different aspects of math in different
fun ways. Simple objects can be used to teach math elements also. Nobel
physicist Richard Feynman told, for example, about how when he was still in his
high chair, his father would bring home color tiles and would line them up in
various ways for (and with) him so that there would be patterns, such as
blue-white-blue-white-blue-white, or color patterns alternating by thirds or
some other way. It was something of just a fun game for the baby, but a game
that had a deeper meaning and point to his father. As long as it stays
interesting or fun for the child, I do not see any harm in it, and it might have
much educational developmental value for later.