Dear Bill and Melinda,
Twenty times the testing may be an understatement for some districts.
My former district (retired) developed its own practice tests for reading and math which was given three times a year (once after regular state testing was done!).
EL students also were tested three additional times (in Spanish), the last battery having to be completed in the same window as state testing.
On top of this, teachers were REQUIRED to test each student three times during the year individually on reading passages. This meant a minimum of 15 – 20 minutes per child while the rest of the class worked independently (more if the teacher had to test a student on a higher or lower level).
A teacher with 33 students (not uncommon in upper elementary) would need a minimum of 10 – 12 hours each cycle to complete this process. This is another 6 days of teaching lost.