The Huntings have two young children (Isabelle age 5; Harry age 3)

The Huntings are concerned about the cost of college education for their two children. The current cost of education is $25,000 per year in todays dollars and the education inflation rate is expected to be 3%. They expect the children to be in school for 4 years each, and while they dont know, they expect any savings for their childrens education to have an average annual return of 8.5%. How much will the Huntings need to be saving each month to reach their desired goals?

I completed the question before, but needed to adjust the terms because of their ages and needed help with it. Both children will attend college at 18 years old.

How much do they need to save per month per child?