Our colleague Mayca B. suggested this link for CAL resources:
http://pluriltybarra.blogspot.com/ (Primary Education)
Thanks Mayca!
The following sites, organized by subject, will give you ideas (content and language) for your classes.
ARTS/TECHNICAL DRAWING
http://www.teachnet-uk.org.uk/2006%20Projects/DT-Technical_Drawing/project-resources.htm
http://42explore.com/draw.htm
http://falcon.jmu.edu/~ramseyil/arteducation.htm
http://www.princetonol.com/groups/iad/lessons/elem/elemlessons.html
http://lessonplancentral.com/lessons/Art/
http://www.billybear4kids.com/Learn2Draw/grid-art.html
COMPUTER SCIENCE AND TECHNOLOGY
http://www.teachervision.fen.com/educational-technology/teacher-resources/43743.html
http://www.csta.acm.org/Resources/sub/DownloadableResources.html
http://www.homeroomteacher.com/computerworksheets.html
http://www.lessonplanspage.com/CIMathGraphingWithMicrosoftExcel68.htm
http://school.discoveryeducation.com/teachingtools/worksheetgenerator/wtg/tech.html
http://vlib.org/Computing
CULTURE
http://www.globalenvision.org/forteachers/26/1220
ENVIRONMENT
http://www.bgci.org/education/links/

GEOGRAPHY AND HISTORY
http://www.theteacherscafe.com/Content_Literacy/Social_Studies_Worksheets.php
http://www.historyteacher.net/
http://712educators.about.com/od/historyworld/World_History.htm
http://members.aol.com/bowermanb/teach.html
http://homeschooling.about.com/od/freeprintables/qt/geogprintables.htm
http://www.instructorweb.com/socialstudies.asp
http://www.tlsbooks.com/fourthgradeworksheets.htm
http://www.education-world.com/soc_sci/geography/index.shtml
http://www.teachingideas.co.uk/geography/contents.htm
http://webtech.kennesaw.edu/jcheek4/geography.htm
LATIN AND GREEK
http://www.dl.ket.org/latin2/mores/
http://people.umass.edu/glawall/grkteach.html
http://ablemedia.com/ctcweb/netshots/latin101.html
http://www.vroma.org/~bmcmanus/marylandtech2.html
http://www.users.globalnet.co.uk/~loxias/lang.htm
http://www.uky.edu/AS/Classics/teaching.html
http://home.rochester.rr.com/latinteach/
LITERATURE
http://www.online-literature.com/subscribe.php
http://litplans.com/
http://www.richmond.k12.va.us/readamillion/literatureactivities.htm
http://www.monmouth.com/~literature/
http://www.sldirectory.com/libsf/resf/bookplans.html
MATHS
http://www.col-ed.org/cur/math.html
http://www.sitesforteachers.com/resources_sharp/math/math.html
http://mathforum.org/library/resource_types/lesson_plans/
http://www.eduref.org/cgi-bin/lessons.cgi/Mathematics
http://www.cloudnet.com/~edrbsass/edmath.htm
http://www.k111.k12.il.us/King/math.htm
http://www.mathworksheetscenter.com/
http://www.ezschool.com/EZSheets/index.html
http://www.mathworksheetscenter.com/mathskills/counting/DrawingToCount/
http://www.schoolhousetech.com/downloads/worksheets/Mathematics.aspx
http://2020ok.com/13884.htm?gclid=CNOJlYmV_pYCFRqH1QodLlBGYA

http://www.lessonplanspage.com/Music.htm
http://teachers.net/cgi-bin/lessons/sort.cgi?searchterm=Music
http://www.theteacherscorner.net/lesson-plans/music/index.htm
http://www.canteach.ca/elementary/music.html
http://www.nhptv.org/Kn/vs/musla2.htm
http://www.lessonplansearch.com/Music/index.html
PHILOSOPHY
http://www.earlham.edu/~peters/philinks.htm
http://www.refdesk.com/philos.html
http://home.pacific.net.au/~greg.hub/philosophy.html
http://www.p4c.org.nz/lessons.html
http://edsitement.neh.gov/tab_lesson.asp?subcategory=7&grade=0
PHYSICAL EDUCATION
http://members.tripod.com/~pazz/lesson.html
http://www.pecentral.org/lessonideas/pelessonplans.html
http://www.geocities.com/Colosseum/3332/index.html
http://www.sports-media.org/
http://www.teach-nology.com/teachers/lesson_plans/physical_ed/
PRIMARY SCHOOL
http://www.primaryresources.co.uk/music/music.htm
http://www.primaryschool.com.au/
http://www.cap.nsw.edu.au/teachers/lesson_plans.htm
http://www.proteacher.com/070009.shtml
http://www.primaryresources.co.uk/
http://www.kinderart.com/kindercolor/
http://www.k111.k12.il.us/King/math.htm
http://www.ezschool.com/EZSheets/index.html
http://www.billybear4kids.com/Learn2Draw/grid-art.html
http://www.tlsbooks.com/fourthgradeworksheets.htm
http://www.homeschoolingadventures.com/worksheets.html
PSYCHOLOGY
http://www.psychlotron.org.uk/
http://jonathan.mueller.faculty.noctrl.edu/crow/activities.htm
http://www.psychology.org/links/Resources/Teaching/
http://www.english-test.net/vocabulary/psychology/psychology_thesaurus.html
http://bestuff.com/stuff/psychology
http://library.csusm.edu/subject_guides/psychology/
http://library.canterbury.ac.nz/psyc/web.shtml
RELIGION AND CATHOLIC MORALS
http://www.studysphere.com/Site/Sphere_5889.html
http://www.4catholiceducators.com/
http://www.silk.net/RelEd/15012kplan.htm
http://catholicism.suite101.com/article.cfm/games_to_play_in_religion_class
http://www.bbc.co.uk/schools/religion/worksheets/
http://www.free-stuff.me.uk/free/education_and_teaching/worksheets/
SPECIAL NEEDS
http://www.teachingheart.net/specialed.htm
http://www.senteacher.org/Print/
http://www.learn4good.com/kids/index.htm
http://www.do2learn.com/picturecards/printcards/index.htm
http://www.dltk-kids.com/coloring.htm
http://www.fisher-price.com/us/fun/coloring/
http://www.wayfinding.net/intrhome.htm
Please, report any broken links!
Source: Raúl Cabezalí. Credit goes to Carmen Medina, from EOI Antequera.