Grind 1,000G 10

(Cross-posted in the Grind 500, Grind 1,000, and Grind 3,000 achievements)

I did not buy the Rooftop level, so this is all based on the School level.

Of course you could always do this in a regular run, just continually head for any rail you can find, grind it, and hope you don't mess up. If you choose to go this route, please take my advice and focus ONLY on grinds if you go this route. Don't try to also get your gap, trick, air, or L-I-N-E achievements in the same run. It's possible to do, but I can guarantee that if you're trying to double-dip (or triple-, quadruple- or quintuple-dip), you will not make it to 3,000. Even focusing on just grinds is not a guarantee, since even if you do it perfectly, you run the risk of random glitches making you fall. I found this to happen in two places. One is in the outside area; there is a long rail in the center lane which goes up, has a short flat portion, goes up another level, has a longer flat portion, and then has two downward portions that mirror the upward portions. This is the same rail that goes above the back-to-back planters which serve as great air ramps. It's not a very diverse level, I'm sure you know what I mean. On this rail, your skater will randomly catch his board on some invisible obstacle at the end of the second rising portion of the rail before the long, flat portion at the top. Ollieing did not help me avoid this. The second glitched area I encountered was inside the school. This second area is hard to resist for grinds, since there is a long handrail in the leftmost lane, followed by a concrete awning which you must ollie up to (at least lvl 2 air needed), and another very long rail. The same invisible obstacle existed at the start of the awning. You can always play it safe by avoiding these two areas, but without the two longest grind segments in the level, you're in for a VERY long haul.

The easier (but more dull) method is to grind this out (ha, see what I did there?) on the tutorial level. Once you reach the point of the tutorial where you are being instructed on how to spin, there will be, in the leftmost lane, a ramp, and a medium-length rail. If you don't spin, the tutorial won't progress. You will pass the ramp and rail, be given the spinning instructions again, and get another chance. If you never spin, this cycle will repeat again and again. If you fall, it doesn't matter, you will just stand back up and keep going, so you can just keep grinding that same rail again and again (without ever spinning) until you finally hit 3,000. Again, this is very boring, and you will have to keep closing the prompt with the spinning instructions again and again every time. But if you can stick with it, the 500, 1,000, and 3,000 achievements will pop eventually, and you can stop worrying about glitched areas in endless runs.