The average salary of substitute teachers in Illinois is approximately $31,000 a year (according to bls.gov) which is about 6% higher than the national average. However it is important to understand that this number can vary greatly as substitute teachers income depends on experience and qualifications and district.
Interest: Not certain of benign twitching due to anxiety. There a few diseases that mimic ALS pretty good: 1) Multifocal motoric neuropathy (MMN) - weakness, fasciculations (not too much) but NO atrophy and very slow progression. 2)Postpoliomyelitic syndrome - Late consequences of poliomyelitis. Weakness, fasciculations, tireness. 3) Myasthenia gravis -no need to comment.
Blood tests to exclude disorders that mimic ALS are also performed. In some instances, a muscle biopsy, which involves taking a small sample of muscle under local anesthesia, is performed. In some cases, genetic tests (performed on a blood sample) can confirm the diagnosis (see Causes/Inheritance).