{"id":641,"date":"2007-03-07T10:08:48","date_gmt":"2007-03-07T15:08:48","guid":{"rendered":"http:\/\/192.168.1.99:8888\/blog\/2007\/03\/07\/1173280128043.html"},"modified":"2007-03-07T10:08:48","modified_gmt":"2007-03-07T15:08:48","slug":"blogentry-teaching-multiplication-and-division","status":"publish","type":"post","link":"http:\/\/blog.morinfamily.com\/?p=641","title":{"rendered":"[BlogEntry] Teaching Multiplication and Division"},"content":{"rendered":"<p>I&#039;ve become somewhat obsessed with teaching Katherine math.&nbsp; At almost 5 years old, I don&#039;t believe that multiplication and division are concepts too difficult to understand.&nbsp; I&#039;ve blogged in the past about the &#034;postfix trick&#034;, where you put the times at the end to make it more understandable &#8212; &#034;How much do you have if you do 3 2 times?&#034;&nbsp; The mental switch there is easier to grasp and you can see &#034;3 and 3&#034;.&nbsp; But this trick gets unmanageable quickly since it&#039;s hard for little brains to grasp numbers much larger (especially if you run out of fingers).<\/p>\n<p>Lately we&#039;ve started working with some flashcards that Nanta and Grampy got us.&nbsp; At first we were going to set aside the multiplication cards as too hard, but after going through the various shape\/color\/letter cards Katherine said, &#034;I want to do those.&#034;&nbsp; She seems to have quickly grasped the tricks for 0 (&#034;if you have 0 of anything, you&#039;ve got 0&#034;) and 1 (&#034;If you only have one of something, then that&#039;s what you have, so if you have one 7, then the answer is 7.&#034;)&nbsp; And I tried the postfix trick for various combinations of multiplying by 2 or 3.&nbsp; Part of the problem is that you quickly run out of fingers, you see.&nbsp; There&#039;s not much that you can multiply by anything greater than 4&#215;2 or 5&#215;2 and still get the answer on both hands.<\/p>\n<p>Here&#039;s a game I plan on trying when I get a moment.&nbsp; I thought of it last night right at bed time so we didn&#039;t have a chance to play it, and I&#039;m bored on the train so I&#039;m writing it up.&nbsp; You&#039;ll need:<\/p>\n<ul>\n<li>10 little plastic Dixie cups, like the sort you hang by the bathroom sink to rinse when you brush your teeth\n<li>at least 20 coins, beans, or other small countable items\n<li>two big bowls (optional)\n<li>marker.&nbsp; Number the cups 1-10.<\/li>\n<\/ul>\n<p>I chose 20 countable items because I think that children my daughter&#039;s age can reasonably work with numbers in that range.&nbsp; The game could easily be expanded up to 100 by simply providing more countable things.&nbsp; So you have to be careful to only choose combinations that result in an answer less than 20<\/p>\n<p>Put all of your countable things into one of the big&nbsp; bowls.&nbsp; You could get by with just piles on the table or floor if you want, I figured the bowl just keeps it a little neater.&nbsp; My 3yr old has a tendency to walk through the middle of such games and mess up the piles.<\/p>\n<p>Pick a flashcard, or just make one up.&nbsp; Say your flashcard is &#034;5 x 3&#034;.&nbsp; The child counts out 5 cups (using the numbers to help, if necessary), and then proceeds to take the items from the big bowl and distribute them, putting 3&nbsp; in each cup.&nbsp; Naturally it&#039;s important at this stage that the child can count to these numbers, but I&#039;m assuming that she can, otherwise teaching her multiplication is a bit overkill.<\/p>\n<p>Once that&#039;s done, dump all the cups into the other big bowl. Now count what&#039;s in that bowl.&nbsp; There&#039;s your answer!<\/p>\n<p>Sure it&#039;s a lot of steps, but the name of the game is for the child to eventually memorize the answers are predict the outcome, and then see if she&#039;s right.&nbsp; You can take turns and let your toddler fill up the cups with beans, and then the adult has to guess at the answer.&nbsp; Then you can figure out together whether you were right by dumping everything out and counting them up.<\/p>\n<p>Division can be taught this way as well, but it&#039;s substantially harder because of fractions.&nbsp; With the help of an adult you can count out a large number of coins, then pick a number of cups that you know divides that number evenly (for instance, pick 12 beans and 4 cups).&nbsp; Then the child can distribute one coin each into the cups until they&#039;re all gone, and look at how many are in each cup.&nbsp; If there aren&#039;t the same number in every cup, that means that the numbers don&#039;t divide.<\/p>\n<p>Like I said, haven&#039;t tried it yet, but I hope to try it soon.&nbsp; I&#039;ll post the results.<\/p>\n<p>&nbsp;<\/p>\n<div class=&#034;wlWriterSmartContent&#034; id=&#034;0767317B-992E-4b12-91E0-4F059A8CECA8:2528294a-f559-4da9-bd7a-5abd893b2e22&#034; contenteditable=&#034;false&#034; style=&#034;padding-right: 0px; display: inline; padding-left: 0px; padding-bottom: 0px; margin: 0px; padding-top: 0px&#034;>Technorati tags: <a href=&#034;http:\/\/technorati.com\/tags\/parents&#034; rel=&#034;tag&#034;>parents<\/a>, <a href=&#034;http:\/\/technorati.com\/tags\/children&#034; rel=&#034;tag&#034;>children<\/a>, <a href=&#034;http:\/\/technorati.com\/tags\/educational&#034; rel=&#034;tag&#034;>educational<\/a>, <a href=&#034;http:\/\/technorati.com\/tags\/diy&#034; rel=&#034;tag&#034;>diy<\/a>, <a href=&#034;http:\/\/technorati.com\/tags\/game&#034; rel=&#034;tag&#034;>game<\/a>, <a href=&#034;http:\/\/technorati.com\/tags\/math&#034; rel=&#034;tag&#034;>math<\/a>, <a href=&#034;http:\/\/technorati.com\/tags\/multiplication&#034; rel=&#034;tag&#034;>multiplication<\/a>, <a href=&#034;http:\/\/technorati.com\/tags\/parenthacks&#034; rel=&#034;tag&#034;>parenthacks<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>I&#039;ve become somewhat obsessed with teaching Katherine math.&nbsp; At almost 5 years old, I don&#039;t believe that multiplication and division are concepts too difficult to understand.&nbsp; I&#039;ve blogged in the past about the &#034;postfix trick&#034;, where you put the times at the end to make it more understandable &#8212; &#034;How much do you have if [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-641","post","type-post","status-publish","format-standard","hentry","category-family"],"_links":{"self":[{"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=\/wp\/v2\/posts\/641","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=641"}],"version-history":[{"count":0,"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=\/wp\/v2\/posts\/641\/revisions"}],"wp:attachment":[{"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=641"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=641"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/blog.morinfamily.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=641"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}