# Resource 4: Units of time

Teacher resource for planning or adapting to use with pupils

 Time1 minute = 60 seconds1 hour = 60 minutes1 day = 24 hours1 week = 7 days1 fortnight = 14 days1 year = 12 months = 52 weeks = 365 daysleap year = 366 days Many timetables and digital watches use 24-hour clock time.Use this scale to change between 12-hour and 24-hour time. 6:15 am  → 06:156:15 pm  → 18:15 Remember:a.m. is morning time (it comes from the Latin ante meridium, meaning 'before midday');p.m. is afternoon and evening time (it comes from the Latin post meridium, meaning 'after midday');the 24-hour clock always uses four digits. Here is a way to remember how many days there are in each month. Start by counting January on the first knuckle of your left hand and February as the gap between the knuckles.All the 'knuckle' months have 31 days.February has 28 days (29 in a leap year).All the other months (April, June, September and November) have 30 days.

Original source: http://www.bbc.co.uk/ schools [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] (Accessed 2008)

Resource 3: Sundials

Section 3: Discussing data