In my child's newest IEP it says she is to spend 400 hours weekly in the resource classroom for reading, writing, and math. The school has been doing standardized testing for the past month, and during that time it looks like she's been getting maybe 25 minutes for just math, and not even everyday. I think they use the classroom for testing for some of the kids. Are they allowed to cut down her hours like that for testing? She's missed out on at least 1000 hours of instruction time due to this. I need suggestions on how to approach this. I'm pretty sure they are already mad at me because I pushed back before the IEP (politely, but firmly which they are not used to from me) because they gave us the exact same goals and an almost copy and past of her current levels from last year.

It appears that you are documenting the missed instructional minutes, which is GOOD.  Ask for an IEP meeting to discuss how the minutes will be made up.  (To answer your question, no, they are not allowed to cut down her minutes due to testing unless it specifically states that in her IEP.)  You don't have to insist on a minute-for-minute replacement (and that may not even be required - depends on your state).  But you can ask for a plan as to how your child will be compensated for this missed instruction.  It could be done by adding on extra time to her pullout sessions moving forward or it could be done by sessions given during the summer, after school, or before school.  Be flexible in what you will accept and hopefully this will not create any tension.  They should know these hours need to be made up somehow.

400 hours is over 16 days (24 hour days).  There is no way she is getting that much instruction in a week.  Most schools are only open to 35 hours a week and they won't take away lunch to provide instruction.  I think you need to get the IEP corrected if it really says 400 hours per week.  Could it be 400 minutes per week?

Not sure how she could have missed 1000 instructional hours.  If school meets for 180 days that are 6 hours long, that's 1080 hours in total.  Again, this isn't realistic for any IEP unless your child is going to school every day.  Could it be 1000 minutes?

I think asking the IEP team to document the IEP minutes your child gets daily is not unreasonable.  And asking them to make up missed time isn't unreasonable either.  I do think you need to get the amount of time in the IEP straight before your write to the school.

If you know how to put 400 hours into a week that typically lasts 168 hours (24 X 7 = 168), please let me know.  I'm behind on some paperwork and could use that extra time to catch up.