Rgvedam bhagavodhyemi yajurvedam samavedamātharvaṇam caturthamitihāsapurāṇam pancamam vedānām vedam pitrya rāśim deivam nidhim vākovākyamekāyanam devavidyā brahmavidyām bhutavidyām nakṣatravidyām sarpadevajanavidyāmetadbhagavodhyemi
Trans.
‘Sir, I know the Rig-veda, the Yajur-veda, the Sama-veda, Atharvana the fourth Veda, as the fifth the Itihasa-Purana, the Veda of the Vedas, the rites of the fathers, Mathematics, the science of portents, the science of Time, Logic, Ethics and Politics, Etymology, the science of the Veda, the science of the Elementals, the science of War, Astronomy, the science of Snake-charming and the fine arts. All this, I know, Sir.’ (p.164)
Source: Chandogya Upanishad and Sri Sankara’s commentary, Trans. By Ganganath Jha, 1923, Madras, the India Printing works
http://archive.org/stream/ChandogyaUpanishadWithShankaraBhashya-EnglishTranslationPart2/04ChandogyaUpanishadWithSankaraBhashya-English-Part2#page/n0/mode/2up
Shankara does not comment upon the list of sciences and arts but focuses on the understanding of brahman.
Ganganath Jha interprets the word as a reference to 'mathematics', in general. In the context of the list elaborated further with reference to elements, astronomy etc. it is not unreasonable to interpret an education in rāśi to include the mathematical computations of path, location and pace of movement or clustering of nakṣatra-s. Perhaps, even the geometrical computations for the construction of vedi had to be part of this rāśi education. Note that the word rāśi is followed by deivam, 'the science of time'. rāśi used in the verse of Ch.Up, can be viewed thus as a 'science of (logical) sets'. nakṣatra-vidyā then becomes a specific discipline of interpreting their contextual inter-relations in space and time. We are searching for 'meanings' as they evolved in time. An extraordinary challenge, indeed, which should humble us.
Namaskaram. Kalyanaraman
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