Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE professor (prof_high_degree VARCHAR, emp_num VARCHAR, dept_code VARCHAR)
TABLE: CREATE TABLE department (dept_code VARCHAR, dept_name VARCHAR)
TABLE: CREATE TABLE employee (emp_fname VARCHAR, emp_num VARCHAR)
TABLE: CREATE TABLE CLASS (prof_num VARCHAR)

### Question ###
Find the first names and degree of all professors who are teaching some class in Computer Info. Systems department.

### Accurate SQL ###

SELECT DISTINCT T2.emp_fname, T3.prof_high_degree FROM CLASS AS T1 JOIN employee AS T2 ON T1.prof_num = T2.emp_num JOIN professor AS T3 ON T2.emp_num = T3.emp_num JOIN department AS T4 ON T4.dept_code = T3.dept_code WHERE T4.dept_name = 'Computer Info. Systems'