Adderall definitely has a "crash" at the end of it. I've found that Vyvanse doesn't do that to me- it's a very smooth and light transition from being active to being inactive. I take Vyvanse in the morning and Adderall in the afternoon, and don't get the Adderall crash, I think because I take them both.

When I was taking just Adderall, my doctor helped me with the crash. If I was taking, say, 20mg 2xday, I would take 20mg in the morning, 10mg or 15mg in the early afternoon, and the remaining 5 or 10 mg in the late afternoon when I noticed it was wearing off. That way, my body wasn't suddenly dropping off after 20 mgs in the late afternoon. Helped me, maybe talk to your doc about it if you think this method could help!