ととべんきのうたの2番が
思い出せず歩いていると
ウンわるく、くらやみのセカイへ
おちてしまったうんちょん。
次から次へとふりかかる
なんもんに答えて、
ぶじにもとのセカイにもどれるか?
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fimg_unchon_walking.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fhole.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fimg_unchon_falling.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fimg_unchon_fallen.png)
![プルルル…](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fimg_mobile.png)
![ん?あれは…](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fstamp_01.png)
![あなに直面するうんちょん](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fimg_hole.png)
![えええ?だれ?](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fstamp_02.png)
![いざ!勝負!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection01%2Fimg_dark_big.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Fnumber_01.png)
トイレの”せんじょうほうしき”は、
あらいおとし式や
サイホンゼット式などいろいろ。
そのうちのひとつ、
「サイホン式」の形はどれ?
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection02%2Fstamp_01.png)
![あなに直面するうんちょん](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection02%2Fimg_water.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Fnumber_02.png)
べんきにたまっている水には、
べんがくっつくのをふせぐほか、
どんなやくわりがある?
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection03%2Fstamp_01.png)
![すべりおちるうんちょん](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection03%2Fimg_slip.png)
![トイレはどんどんしんかいしてるんじゃ!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection03%2Fimg_dark_big.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Fnumber_03.png)
今から約40年前には、
1回ながすごとに20リットルの水を
しようしていたトイレ。
さいしんがたのトイレでは何リットルに?
![よーし!次も!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection04%2Fstamp_01.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection04%2Fbg_uzumaki.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection04%2Fimg_dark_nuu.png)
![ぬぅ...次のもんだいはこれだ!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection04%2Ftxt_dark_nuu.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Fnumber_04.png)
いぜんは家のなかで一番水をつかうものといえばトイレでしたが、
2位にランクダウン。変わって1位になったのは?
![ぼくって天才!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection05%2Fstamp_01.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Fnumber_05.png)
トイレで用をたしたあとは、紙でふいたり、
お湯でながしておしりをせいけつにたもちます。
では、そのむかし、日本人は何でおしりをふいてた?
![でもほんとうは、おさつがいいなぁ...ウンチドリーム](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection06%2Fstamp_01.png)
![くぅ〜っ!ちょうしにのなよぉ!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection06%2Fstamp_02.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection06%2Fstamp_02_sp.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Fnumber_06.png)
ふつうのべんきよりも、よこはばが5cm、ながさがやく7cm
大きいべんきがあります。
これ、だれのためにつくられたもの?
![アレ?もうさいご?つんまんないの〜](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection07%2Fstamp_01.png)
![おのれ〜!なまいきなヤツめ!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection07%2Fstamp_02.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection07%2Fstamp_02_sp.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Fnumber_07.png)
日本人のおしりの大きさをけんきゅうし、
今の形におちついたノズル。
そこにかくされた、いがいなヒミツとは?
![...まけたよ。](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection08%2Fstamp_01.png)
![なんてな!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection08%2Fimg_dark_big.png)
![手をかざすダークうんちょん](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection08%2Fdarkunchon_tornadesenjyo.png)
![くらえ!トルネードせんじょうだ!](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection08%2Ftxt_dark_tornade.png)
![ながされるうんちょくん。](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection08%2Fimg_unchon_tornade_01.png)
![しわわーっ](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection08%2Fimage_unchon_tornade.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Ficon_seikai.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Ftop%2Fimg_study_nanafushigi.png)
サイホン式は水を吸い出す作用とうずまき作用が合体した洗浄方式で、音が静かなのが特徴だよ。水のたまる面が広いので、便がすいちゅうにしずみこむぶんにおいも少なくなるんだ。
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fcommon%2Ficon_zannen.png)
![](https://toto.imagewave.pictures/%2Fkids%2Fassets%2Fimages%2Fstudy%2Fnanafushigi%2Fsection03%2Ficon_dark_01.png)