DD took it at ages 9 and 10. We felt like "serious" prep would undermine what we wanted her to get out of it, so we didn't do a lot. The one thing we did both years was print out practice sections for math and have her work for 30 minutes (one practice each year). The goal there was just to give her a feel for time management since she'd never had to skip a problem or manage her time on state tests. It didn't generalize well enough for her to actually manage her time on the EXPLORE (but that's a longer post

). I do think it probably allowed her to participate on test day without freaking out after not finishing a section. If you are prepping for that reason, I'd suggest ignoring the EXPLORE sample items and instead googling "released test items" and 8th or 10th grade (whichever will have problems on it that your kiddo might not know). That will allow you to print out a longer set of problems that may be slightly more representative of the type of work on the test. I chose to print out more problems than she could possibly finish in the 30 minutes and made sure there were problems she couldn't do yet. I prefaced the practice time by talking to her about identifying when she should skip and come back to a problem, and that was the extent of the follow up conversation too. We only checked accuracy on problems that weren't guesses--I didn't want to do "instruction" as prep, again, because that would have undermined what we personally wanted from the test. The exception was that I was willing to explain unfamiliar vocabulary since she sometimes had the concept but hadn't been exposed to the specific vocabulary of it.