Ethandioic acid (also known as oxalic acid) is a chemical compound with the formula H2C2O4. This dicarboxylic acid is a relatively strong organic acid. This acid is widely used as an purifying agent in pharmaceutical industry.
(Source - http://en.wikipedia.org/wiki/Ethandioic_acid)

However, ethandioic acid is very poisonous.

Oxalic acid is a strong poison. The toxic symptoms from ingestion include vomiting, diarrhea, and severe gastrointestinal disorder, renal damage, shock, convulsions, and coma. Death may result from cardiovascular collapse. Oxalic acid may be absorbed into the body through skin contact. It is corrosive to the skin and eyes, producing burns.
(Source - http://www3.fed.cuhk.edu.hk/chemistry/oxalic.html)

If the purpose of the practical work is merely to prepare a standard solution, then the use of toxic ethanedioic acid is not essential. If you really want to prepare a primary standard of an acid, potassium hydrogen phthalate (C8H5O4K) is much better than ethandioic acid. It is a monoprotic acid (HOOCC6H4COO- K+) with low toxicity. Potassium hydrogen phthalate is a good primary standard because of the following properties:

1. High purity
2. Stable in air
3. Easily soluble in water
4. High molar mass
5. Complete and rapid acid-base reaction

I can't find the exact procedure on how to use ethandioic acid to determine the concentration of an acid anywhere. Can someone enlighten me on that?