MATEMATICAS PARA 2do. SUMAS, RESTAS, MULTIPLICACIONES Y PROBLEMAS

• http://ares.cnice.mec.es/matematicasep/a/1/ca1_08.html
• http://www.genmagic.net/educa/mod/resource/view.php?inpopup=true&id=63
• http://www.genmagic.net/educa/mod/resource/view.php?inpopup=true&id=70
• http://www.genmagic.net/educa/mod/resource/view.php?inpopup=true&id=68
• http://www.genmagic.net/educa/mod/resource/view.php?inpopup=true&id=67
• http://www.genmagic.net/educa/mod/resource/view.php?inpopup=true&id=62