Is this acceptable form for my resume?

I have been a stay at home mom for 7 years. Being out so long is hard enough when it comes to reentering the work force, but I also think my resume is working against me.

I went back to work part time as a Teaching Assistant last year when my daughter started Kindergarten just to have something to do that worked with her school hours.

Now I’m ready to go back to work full time, but I hate how my resume looks with “Teaching Assistant” listed first. Currently, it is Teaching Assistant, then volunteer board positions I held while staying home, then Office Manager.

Is it ok to reverse the chronological order so Office Manager is first and, therefore, most noticeable? It is definitely the most relevant to the type of position I am seeking.