http://www.transum.org/Maths/Activity/Reading_Scales/ Skaalad
http://www.ictgames.com/mostlyPostie.html Kaalumine
http://coolsciencelab.com/stop_the_clock_harder.html Kell
http://www.sheppardsoftware.com/mathgames/round/mathman_round_hundreds.htm Ümardamine sajalisteni
http://www.sheppardsoftware.com/mathgames/round/mathman_round_thousands.htm Ümardamine tuhandelisteni
