If you are under 40, you can get a student allowance for tertiary study for up to 200 weeks. If you are 40 or over, you can get it for up to 120 weeks. These are lifetime limits for your student allowance.You can get a student allowance for up to 92 weeks for secondary school study.able: You, your partner, your children and your student allowance. You, your partner and your children. The most student allowance after tax you could get, at 'M' rate. 1  Your combined income is more than $423.92 and less than $882.98 a week before tax.