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'''Reading an analog clock''' is typically hard for young learners in primary school as well as for people suffering from dementia.<ref>Sunderland, T., Hill, J. L., Mellow, A. M., Lawlor, B. A., Gundersheimer, J., Newhouse, P. A., & Grafman, J. H. (1989). Clock drawing in Alzheimer's disease: a novel measure of dementia severity. ''Journal of the American Geriatrics society'', ''37''(8), 725-729.</ref> In [[Decoding the Disciplines]] clock reading often serves to exemplify the process of Decoding.<ref name=":0">Riegler, P. (2025): [[The Decoding Clock Reading Activity]]. Didaktiknachrichten, Issue January 2025, in press<br /></ref>
'''Reading an analog clock''' is typically hard for young learners in primary school as well as for people suffering from dementia.<ref>Sunderland, T., Hill, J. L., Mellow, A. M., Lawlor, B. A., Gundersheimer, J., Newhouse, P. A., & Grafman, J. H. (1989). Clock drawing in Alzheimer's disease: a novel measure of dementia severity. ''Journal of the American Geriatrics society'', ''37''(8), 725-729.</ref> In [[Decoding the Disciplines]] clock reading often serves to exemplify the process of Decoding.<ref name=":0">Riegler, P. (2025): [[The Decoding Clock Reading Activity]]. Didaktiknachrichten, Issue July 2025</ref>
[[File:Reading a clock 1741765815651.jpg|thumb|266x266px|Clock from 1754 at Irsee Abbey, Germany. What time does it show?]]
[[File:Reading a clock 1741765815651.jpg|thumb|266x266px|Clock from 1754 at Irsee Abbey, Germany. What time does it show?]]


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* There are two scales on an analog clock. A coarse one counting the hours from 1 to 12 in steps of 30° and a finer one counting minutes and seconds from 0 to 59 in steps of 6°.
* There are two scales on an analog clock. A coarse one counting the hours from 1 to 12 in steps of 30° and a finer one counting minutes and seconds from 0 to 59 in steps of 6°.
* If there is a fast moving hand, ignore this one for the time being, although it typically catches one's attention first.
* If there is a fast moving hand, ignore this one for the time being, although it typically catches one's attention first.
* To determine the hour, locate the hour hand. This is usually the shortest hand. Read the position of this hand on the scale from 1 to 12. If the hand is between two such position take the smaller value.
* To determine the hour, locate the hour hand. This is usually the shortest hand. Read the position of this hand on the scale from 1 to 12. If the hand is between two such positions take the smaller value.
* To determine the minutes, locate the minute hand. This is usually the larger hand. Read the position of this hand on the scale from 0 to 59.
* To determine the minutes, locate the minute hand. This is usually the larger hand. Read the position of this hand on the scale from 0 to 59.
* While the lengths of the hand usually allows to locate hour and minute hand, the length of the hands is neither a necessary nor a sufficient conidition. Actually there is a necessary relation between the angle of the two hands: The fractional part by which the minute hand is located between two adjacent hour markers is determined by the position of the minute hand. For instance, at 5:00 the hour hand is exactly at 5, at 5:15 it moved a quarter of the disctance to 6, while at 5:30 it is exactly between 5 and 6.<ref name=":0" />  
* While the lengths of the hand usually allows to locate hour and minute hand, the length of the hands is neither a necessary nor a sufficient conidition. Actually there is a necessary relation between the angle of the two hands: The fractional part by which the minute hand is located between two adjacent hour markers is determined by the position of the minute hand. For instance, at 5:00 the hour hand is exactly at 5, at 5:15 it moved a quarter of the disctance to 6, while at 5:30 it is exactly between 5 and 6.<ref name=":0" />  
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<references />
<references />
[[Category:Reading]]

Latest revision as of 20:41, 22 January 2026

Reading an analog clock is typically hard for young learners in primary school as well as for people suffering from dementia.<ref>Sunderland, T., Hill, J. L., Mellow, A. M., Lawlor, B. A., Gundersheimer, J., Newhouse, P. A., & Grafman, J. H. (1989). Clock drawing in Alzheimer's disease: a novel measure of dementia severity. Journal of the American Geriatrics society, 37(8), 725-729.</ref> In Decoding the Disciplines clock reading often serves to exemplify the process of Decoding.<ref name=":0">Riegler, P. (2025): The Decoding Clock Reading Activity. Didaktiknachrichten, Issue July 2025</ref>

Clock from 1754 at Irsee Abbey, Germany. What time does it show?

Description of bottleneck[edit | edit source]

People find it hard to read of the information coded by the hands of a clock and translate this information into a valid description of clock time.

Description of mental tasks needed to overcome the bottleneck[edit | edit source]

  • There are two scales on an analog clock. A coarse one counting the hours from 1 to 12 in steps of 30° and a finer one counting minutes and seconds from 0 to 59 in steps of 6°.
  • If there is a fast moving hand, ignore this one for the time being, although it typically catches one's attention first.
  • To determine the hour, locate the hour hand. This is usually the shortest hand. Read the position of this hand on the scale from 1 to 12. If the hand is between two such positions take the smaller value.
  • To determine the minutes, locate the minute hand. This is usually the larger hand. Read the position of this hand on the scale from 0 to 59.
  • While the lengths of the hand usually allows to locate hour and minute hand, the length of the hands is neither a necessary nor a sufficient conidition. Actually there is a necessary relation between the angle of the two hands: The fractional part by which the minute hand is located between two adjacent hour markers is determined by the position of the minute hand. For instance, at 5:00 the hour hand is exactly at 5, at 5:15 it moved a quarter of the disctance to 6, while at 5:30 it is exactly between 5 and 6.<ref name=":0" />
  • If there is a fast moving hand, it indicates the seconds analogously to the minute hand.

Related scholarly work on this bottleneck[edit | edit source]

The paper The Decoding Clock Reading Activity describes the origin of the activity and provides materials.

People interested in this bottleneck[edit | edit source]

Christian Kautz, Peter Riegler

Available resources[edit | edit source]

References[edit | edit source]

<references />