Theme: ADDED (Parse it as ADD ED) (65. Extra, and a two-word hint to the answers to the starred clues)
17. *Teachers who demand perfect asanas?: YOGA PEDANTS. Yoga pants.
24. *Blogs and newsletters about raising a family?: MAMMA MEDIA. Mamma Mia.
49. *Lion or tiger in the National Zoo?: FEDERAL CAT. Feral cat.
58. *Ocean predator taking whatever comes its way?: MAKEDO SHARK. Mako Shark.
C.C. here. Lemonade had some computer issues and could not access his write-up. When he's back online, I'll copy and paste his writeup here.
If you have any questions, please ask in the Comments section.
Across:
1. Blood relative?: FLESH.
6. Like a WiFi-enabled toaster: SMART.
11. Storage acronym: ROM.
14. "Always Innovating" infomercial brand: RONCO.
15. Pointed, in a way: TINED.
16. AQI monitor: EPA.
19. High pts.: MTS.
20. Acrylic alternative: ENAMEL.
21. California's Big __: SUR.
22. Word with hot or fine: MESS.
23. Semi: RIG.
27. Gets: SEES.
29. Notable time: ERA.
30. Wickerwork: CANING.
31. Fancy-free adventures: LARKS.
33. Willing subject?: ESTATE.
34. City on the Rhine: BASEL.
37. Recital pieces: SOLOS.
38. Confirmed, in a way: UPHELD.
40. Farm machine: BALER.
43. Exactly right: SPOT ON.
44. Mike and __: IKE.
45. Inbox clogger: SPAM.
51. Mendes of "Girl in Progress": EVA.
52. Actress Cheryl: LADD.
53. Hägar creator Browne: DIK.
54. Area that's far from a strike zone: GUTTER.
57. Inventor Whitney: ELI.
60. Summer along the Seine: ETE.
61. "SNL" alum Cheri: OTERI.
62. Nightingale, notably: NURSE.
63. Sci-fi/fantasy publisher whose logo is a mountain peak: TOR.
64. Velvety garden flower: PANSY.
Down:
1. Young chickens: FRYERS.
2. Coin that's for the birds?: LOONIE.
3. Order from Captain Picard: ENGAGE.
4. Many a "We've suspended your account" text: SCAM.
5. Pandora's box remnant: HOPE.
6. Benchmark: Abbr.: STD.
7. Oppressive atmospheres: MIASMAS.
8. Per __: ANNUM.
9. Go back over: RETRACE.
10. XFL scores: TDS.
11. Like some skill-building classes: REMEDIAL.
12. Joins: OPTS INTO.
13. Treatments that many are prone to enjoy?: MASSAGES.
18. Bull on a glue bottle: ELMER.
22. Life guides: MENTORS.
25. Synagogue structure: ARK.
26. Shot not allowed in some pool halls: MASSE.
28. Came down hard?: SLEETED.
32. __ nothing: ALL OR.
34. After-school lineup: BUS FLEET.
35. Entrance: APPEAL TO.
36. Less liable to last: SHODDIER.
39. 23andMe's stock in trade: DNA DATA.
40. Quarrels: BICKERS.
41. Pseudonym letters: AKA.
42. Free: LET GO.
46. "Hoist with his own __": Hamlet: PETARD.
47. Unwilling: AVERSE.
48. Prominent: MARKED.
50. Compare: LIKEN.
55. Sch. where John McCain is buried: USNA.
56. Dull sound: THUD.
58. Custodial need: MOP.
59. Handy initials: DIY.